As of right now, VR by far.
I used to fantasize about VR a decade ago. I have great "modern nostalgia" for that era of VR between late 2013 and around mid 2016 where I'd regularly watch VR reaction videos of people falling over, freaking out at extremely basic rollercoaster rides. Kind of like a modern version of that apocryphal tale of how audiences ran away from that movie of a train arriving at a station circa 1896, except real because there were loads of videos about it. And this for the Oculus Rift devkit, not even the consumer version.
I never watch ecelebs so I couldn't tell you much about the lore of Markeplier or Jacksepticeye, but you can bet I watched their Rift videos as well as other smaller YouTubers' videos constantly.
Back on the old forum and KurzweilAI, we'd fantasize and speculate about VR often. Remember when we were sure that CV1 was definitely going to launch with 4k screens and foveated rendering in 2014, 2015 at the latest? Heck we even prescribed unrelated developments to VR— a 4k phone that was shown off around 2014 was "obviously testing for a 4k Rift" and showing that it was technically possible; GTA5's first person mode was "obviously" meant to take advantage of VR; that movie Oculu was a thinly veiled hype piece for the Rift!!
We had mobile VR scams meant to fill the void too. I remember even thinking that it was the Future
because you could buy a mobile VR headset at a dollar store. And I'd just daydream about using VR to recapture that nostalgic "feeling of mind" I had at times in my childhood, imagining a far future iteration that would let me reexperience my childhood reconstructed through my memories, other's recollections of the same area, and archival news.
So frenzied was that hype that people heralded VR as the next step in human evolution and would get violently defensive against claims it was overhyped.
There was all this boundless optimism and excitement over what VR might be.
MIGHT be.
Because as the reality played out ever since my first rumblings of VR hype watching that Oculus Rift Mirror's Edge playthrough almost exactly a decade ago now, it's just not there yet.
All the critics saying VR was dying or is dead aren't true. VR isn't dead until it's rotting in the state of near nonexistence it was in between 1997 and 2012, where worldwide yearly headset sales could be measured with triple digit numbers.
But the much more reasonable criticism that it needed another decade of hardware improvement before primetime seems to have proven true. Last gen VR debuted at least 8 years too soon. The only benefit was triggering a huge wave of software development so that there'd actually be something there as a foundation for when VR relaunches in a much more capable state. But otherwise, VR has been a grave disappointment. It's lucky that the hardware and software to make it profitable exists. If the Rift took off in the 2000s, I think investment would dry up to deathly levels.
When you can buy the Quest 2 at a dollar store— new, unused, as an afterthought purchase of $49— then that is when I'll say VR is both not prohibitively expensive to get into and has enough juice to create immersive experiences. When the Varjo XR-3 is a standard $399 headset, then I'll figure that the hardware is able to realize its early promises of incredible immersion. When you can get VR goggles that don't feel uncomfortable to wear, that's when it won't look too goofy to use.
And the final frontier is a neurocontroller rather than just motion controls.
Until then, it's certainly my pick for "most hyped tech that had the least impact" that's not vaporware.