Jason Scott is a “guerilla internet archivist”. Someone’s got to be. If you’ve got some content embedded in a site that’s about to disappear, then he and his team of coders and data engineers go in there and “Ocean’s Eleven” the joint. In the name of digital archaeology, they migrate as much data as they can to a safe harbour even as the main site goes down. “We swoop in and, to the best of our ability, take a snapshot,” he says.

Scott is interested in conserving the stuff we have forgotten has value. Increasingly, our culture plays itself out on the internet, yet even now we have a tendency to view what we do on there as trivial. Or we make the mistake of assuming that digital means for ever. “The problem is, the internet’s systems have been designed as though everything goes on indefinitely,” he says. “There are no agreed-upon shutdown procedures. When users die, what do you do? Because their accounts live on, and suddenly Facebook is telling you your dead friend also likes Snickers bars. Often, you don’t even know who’s running a site. It’s as if you didn’t know who was in charge of your water supply; then one day, it just stopped ...”

As one of the earliest adopters in the pre-world wide web 1980s, Scott took thousands of screenshots of bulletin-board systems – early internet message-boards. In 1996, he decided to share his ASCII joy by building a website to host them all: textfiles.com. It’s still online today, a piece of retro-within-retro. The site made Scott famous in net-nostalgia circles, and its legacy has made him one of the key movers in how we interact with and conserve an online kingdom, parts of which feel as faded as any Mayan temple.

Scott now works for archive.org. This is the new, broader umbrella for what used to be called the Wayback Machine, the online library that can show you what a given website looked like on any given day, now encompassing more than 279bn pages. Its $18m (£14.5m)-a-year running costs are funded chiefly through donations, averaging $25 a time. Alongside Jimmy Wales’s Wikipedia, the Wayback Machine feels like a relic of a kinder, gentler era in the life of the net – before Facebook algorithms were squeezing every penny out of your newsfeed. It was, we were told, a soft-libertarian wonderworld, full of dreamers who believed that private donations plus low information costs would breed a web where we were all equal, all beautiful.

It hasn’t quite turned out like that. Which could be one reason we now look back so mistily at the web of olden times. Even in 2001, there were back-to-the-landers recreating the revolving Roman columns, dolphin gifs and mismatched spinning comic sans of the Geocities age. By 1999, Geocities was the third-most visited website in the world, enticing a vast quilt of hobbyists to make their own pages about whatever interested them. When it finally shut its doors in 2009, the Wayback Machine made a complete copy of it. But nostalgia for what it represented means that there’s also Neocities – an attempt to reboot its elemental qualities. Not to mention the Geocitiesizer – which recreates the rest of the web in the same garish colours, autoplaying Midi-songs and intrusive tiled windows. Internet artist Olia Lialina has created One Terabyte of Kilobyte Age – which serves up an unending spool of Geocities page screengrabs in the form of a Tumblr blog.

Go back another generation in internet nostalgia and you hit Tilde.club – a website-building engine with a lengthy waiting list, where learning a few coding skills will allow you publish some authentically rough, poorly spaced web pages from the mid-90s. In addition to these retro sites, there are emulators to recreate the blocky tedium of waiting for 56k modem to serve a page. Then graphics patches to simulate the graininess of old cathode ray screens. These are often sinkholes of processing power. Making something look slightly grainy and a bit off is, it turns out, unbelievably energy-consuming.

An old webpage as seen on the One Terabyte of Kilobyte Age blog.

This nostalgic impulse is also playing out in the real world. Last year, AMC’s much-admired but little-watched Halt and Catch Fire took the early internet era and dramatised it, one IRC chat log at a time. In music, the now-fading vaporwave movement imbued the silvery cyber-joy of the early internet with lashings of melancholia, as a generation that had come of age alongside the net began to look back and wonder where their dreams had gone.

Perhaps we’re experiencing this boom in nostalgia because there’s suddenly so much more retro to go around, and easier access to it. Or perhaps it’s because the innovation curve seems to have plateaued; today’s web giants are between 10 and 20 years old, and much of the past five years has been about tweaks, consolidation and monetisation of previous business plans. There’s also a sense that we’ve come through a lot of collective mental evolution in the past few years – from an age where each new social network filled us with naive joy at the possibilities for connection, to an era of subtweets, dogpiling and virtue signalling.

Scott isn’t convinced. “In the final analysis, people will hook their own nostalgia on to their own brains very effectively, regardless of when the technological platform started. ‘Oh, remember when we were all on Netflix? Remember when Twitter was just this little club?’ In the life of any platform, there’s always an early-adopter phase, where the people who were there first get annoyed by the people who have arrived later.”

It’s also wrong to assume that your cherished experience is everyone’s – nostalgia rapidly becomes obscure hieroglyphs if you’re outside its target market.

“One day on textfiles.com, I put up a whole lot of ‘under construction’ gifs that I’d taken from Geocities,” says Scott. “And I’d watch as people linked to them. Some of them said: ‘Hey, remember these?’ But others said: ‘I’ve never seen this before. Why did people do this?’ Then an art museum got in touch and said: ‘We want to make a wall of them as an art exhibition.’ People didn’t have any connection to them – they’d go ‘wow’ or ‘what is this?’, but it had become about as meaningful as someone making a dress from an old phonebook. It had fallen down into this general mulch of human culture.”

The mulch is vast and every layer obscures another. We’re all eating and excreting so much culture now that it has become very hard to keep tabs on it. The team at archive.org are presently recording all US TV, 24/7. One team member recently phoned the White House switchboard to record every different voicemail message on there – just to have a database of what it sounded like in 2016.

But while the team try not to make too many editorial decisions, they have to accept that not everything can be preserved. Even if it is just chucking out the washing powder ads on all that TV coverage and just keeping one version, compression must come, and that means stuff will inevitably get lost along the way. Scott shrugs. “Life,” he admits, “is a lossy format.”

• This article was amended on 7 February to clarify that Jason Scott posted Geocities “under construction” gifs to his site textfiles.com, not archive.org