As you may have already heard, starting on December 17, Tumblr will no longer allow porn on its platform. This will hurt the sex workers and communities of people who enjoyed sharing and consuming NSFW content on the platform. But many people have also suggested it might be the beginning of the end for Tumblr, which, perhaps because it has traditionally catered to adult communities, has largely come to be identified with porn.

But how much porn is on Tumblr, anyway? Last year, two Italian universities and Bell Labs attempted to find out. According to their study, published in January 2017, only about .1 percent of Tumblr’s users account for the porn that’s available on Tumblr.

But shockingly, they found that roughly a quarter of Tumblr users were on the platform largely to consume pornography.

This study was based on the behavior of 130 million users, about half of Tumblr’s entire user base. Of that number, “adult content consumers are 22 percent of our sample,” the study said.

“At the time of the study, roughly 30 million active accounts were consuming adult content, either re-sharing it or following the accounts of those producers,” Luca Aiello, one of the study’s authors and now a senior research scientist at Nokia Bell Labs told Motherboard in an email. “I expect this audience to experience a noticeable drop in engagement: some of them will just churn out, many of them will likely reduce considerably the time spent on the platform.”

Another 28 percent, or roughly 40 million users, encountered pornography unintentionally on Tumblr. That means they didn’t seek out the porn, but they followed someone who pushed it into their feed. “The extent of this exposure is hard to estimate but it's probably not major,” Aiello said. “Therefore, I believe some people in this segments would be happy to have a cleaner Tumblr feed but I don't expect a significant lift in their engagement, overall.”

Crucially, the study found that Tumblr's userbase was more female than many social networks ("we estimate that the average user age is 26 and 72 percent of the users are female," they wrote.) They found that these demographics held up between porn consumers and non porn consumers on the site, and that, in fact, young women between the ages of 20-25 were consuming porn on the site at a higher rate than young men. This means that Tumblr's crackdown will likely disproportionately affect women porn consumers.

“A lot of women I’ve spoken to say they discovered porn while fumbling around on Tumblr,” Glamour wrote in an article detailing the ways Tumblr became a safe space for women to find pornography online.

The quick gifs, soundless fucking, and curated nature of the platform lent itself to becoming a great way for people to trade and consume pornography safely. “The structure of a social network is fundamentally related to the interests of its members,” the study explained.

It didn’t have to be this way. According to Aiello, Tumblr could have easily kept the porn and done a better job of moderating its platform. “Sensitive content could be effectively restricted to its community of interest and masked to the rest of the world,” he said. “Flickr is a very good example of that: it contains adult content but the general public doesn't even know it because there are very effective controls and filters in place.”

Tumblr attempted this last year, by turning “Safe Mode” on by default. But it bungled that rollout, and has continued to bungle the moderation of its content. Now, it is banning NSFW content, and it’s almost surely going to push the roughly 100,000 porn “producers” away altogether: “the people controlling those accounts will most likely abandon the platform: there would be no reason for them to use a service that forbids adult posts,” Aiello said.

Different platforms are good at different things. Twitter is a great place to fight with strangers you don’t know and generate non-sequitur comedy gold. Facebook is great for keeping up with family and fomenting genocide. Tumblr was great at disseminating pornography. Without that, what is it even for?