Quoted from colonel_caverne:
saw it yesterday in 3D and ICE techno (sound dolby atmos, laser 4K..) and pretty disappointed with 3D or not really impressed with it. Got the feeling that 3D technology has not been improved since many years.
I think that's where the benefit of HFR (high frame rate) comes into play, it really helps with the 3D affect. Without HFR the 3D affect has seemed a bit dull and even a bit blurry IMO. I'm not a fan of the fast motion look but it's not super noticeable in Avatar 2 versus say the Hobbit HFR 3D versions.
“High frame rate is available; We’re using it as an authoring tool to improve some of the 3D, but we’re not just broadly applying it as a format”. Cameron emphasized that HFR was applied sparingly. “We created new 48 frames-per-second inter-frames to smooth out some of the strobing and some of the rapid cameras moves – during the viperwolf chase, the Thanator chase, things like that – to improve the stereoscopic experience”. But again, in Avatar 2 almost this whole masterpiece was an HFR. Indeed, in our opinion, the HFR improves the feel of 3D, makes it more beautiful, and prevents eye fatigue, which is essential for a three-hour movie.