It’s easy to forget the impact that Avatar, James Cameron’s outlandish space fantasy about a paraplegic soldier who travels to another world and falls in love with an alien princess, made in 2009. This is the movie that singlehandedly ushered in the 3D revolution; saw fans scrambling to see it three, four or more times, and which had studios scrambling desperately to shoot their tentpole offerings in stereoscope.

Debate raged in the early 2010s about whether 3D was really worth the extra money, especially for those who claimed it simply gave them a headache. Cheap conversions such as 2010’s Clash of the Titans, featuring battling gods and goddesses who often seemed to have been physically glued to the screen, did not help matters. Cameron himself spent a great deal of time talking about how terrible everybody else’s efforts at 3D were, which probably helped in the long run but also contributed to the feeling that audiences were being cheated into parting with extra wonga by shady studio execs. Still, the 3D revolution, however you viewed it, was at the centre of the zeitgeist, with Avatar’s staggering success its defining catalyst.

The best part of a decade on, and things seem a little different. Of the Top 10 movies released in the UK in 2016, eight were available in stereoscope, so the idea that 3D was merely a flash in the pan is nonsense. Yet there is also a sense that wannabe blockbusters no longer sink or swim depending on their ability to offer viewing in the format. Would 2016’s top movie, Rogue One: A Star Wars Story, have made a few million less had it not been available in 3D? Perhaps, but the movie would still have been a spectacular smash due to strong reviews and excellent word of mouth. The same goes for JK Rowling’s Fantastic Beasts and Where to Find Them, which came in second. The top UK film of 2015, James Bond adventure Spectre, was not even released in 3D.

Meanwhile, Cameron himself is beginning to sound a little defensive when it comes to discussing the ever-widening gap between Avatar part one and A. He still has the confidence to plan three further episodes (that will be released in December 2021, 2024 and 2025 respectively). But it’s fair to ask the question whether, this long after the original’s groundbreaking impact, there is palpable demand for more fun with the Na’vis and their swishy, USB-compatible tails.

It’s not just perception of Avatar’s achievement with 3D that has changed over time. The movie was so successful – it still stands as the highest-grossing of all time worldwide when tickets are not adjusted for inflation – that it has been analysed and picked over so repeatedly by raptor-like armchair critics that its gleaming bones were long ago exposed. Cameron has fought off numerous lawsuits from artists and screenwriters who claimed the Titanic film-maker stole their ideas, but there remains a nagging suspicion that the plot of Avatar borrowed more surreptitiously from less litigable source material: the epic Kevin Costner western Dances With Wolves or the animated musical FernGully: The Last Rainforest, for instance, both of which feature native tribes who come under threat from outsiders and a central romance between a local female and a sympathetic member of the invading race.

Eyes on the prize … director James Cameron at the US premiere of Avatar, 2009. Photograph: Robyn Beck/AFP/Getty Images

One might also argue that the idea of slipping into another creature’s skin through the power of technology cribs much from video games. But the recent failure of Assassin’s Creed to light up multiplexes surely proves that the inclusion of such ingredients doesn’t guarantee a film’s success. Even if it was not, ultimately, the most original vision in American cinema of the 21st century, Avatar was at least an indisputable smash.

There remains the issue, however, of the film’s failure to flourish as an object of cult fandom. Given its huge reach, there has been little online clamour for a sequel; little sense that audiences are desperate to find out more about the forest moon of Pandora and its inhabitants. Perhaps that is because, unlike most modern Hollywood movies in the era of endless sequels, anti-climactic finales and cinematic universes, Avatar ended rather satisfyingly with most of the major threats eliminated. There have been hints that Stephen Lang’s Colonel Quaritch will be back in part two, despite being struck by a pair of Na’vi arrows in the first movie, and everyone is expecting the surviving employees of Earth’s nefarious Resources Development Administration to return for revenge in the sequel. Yet there has been relatively little speculation as to where Cameron will take things next – perhaps because the first movie left so few clues.

The contrast with, for example, the current Star Wars trilogy, is remarkable. There are entire YouTube channels and blogs devoted to speculating on what might happen in the first 10 minutes of Star Wars: The Last Jedi, even though far fewer people worldwide saw JJ Abrams’ The Force Awakens than caught Avatar in the cinema.

On the other hand, perhaps we should be thankful that Cameron and his team have chosen the more dangerous path, of carefully-crafted world-building, rather than rushed production schedules and inevitable reshoots. We need only look at the examples of ultimately disappointing franchises such as The Matrix, The Hobbit and DC’s current Extended Universe (the excellence of Wonder Woman notwithstanding), to see what happens when the need to hit deadlines forces studios to debut their latest work before it is truly ready.

In retrospect, Avatar may not have been quite as epoch-defining a piece of cinema as it seemed in 2009. But Cameron remains a masterful genre film-maker, the creator of superlative sequels to both his own best sci-fi work (Terminator/Terminator 2) and that of others (Aliens). When all the cosmic dust has settled on the Pandora’s box of winged, six-legged beasties and 9ft-tall blue space creatures, there remains every chance that the Canadian director will have adeptly batted aside his critics, just as the Na’vi sent Quaritch and his crew crashing back down to Earth. If he concedes in transforming Avatar into more than the sum of its parts over another 12-hours-plus of brain-bamboozling stereoscopic space fantasy, we will most definitely have it coming.