no, that's just poor motivation and lack of drive.
Anything is possible if you got the skill, motivation and drive. More importantly the assets, source code and a good team.
just because it's by fan(s) doesn't automatically mean/make it impossible.
If someone's actually remaking all of this, why not just make the game in 3D? The pre-rendered backgrounds were just because of the hardware limits of the time. You could easily have the same scenes and same camera angles with proper 3D scenes.
Switch is a great platform for those PS1 games. If you play it in handheld mode, the low resolution of the backgrounds won't be as evident.
Everything else about FF9 has aged really well, especially given that they updated the character models!
Unfortunately, from what people are saying, the Switch version seems to still have bugs that were in previous ports (PC/PS4 and mobile) - music starts from the beginning after battles, rather than picking up where it left off, and there's a lack of true analog control (ie, you can use the analog stick, but you only move in eight directions). I was really looking forward to picking this up, but those issues are giving me pause. For the time being I think I may hold off on this one, especially since I still have my PS1 discs; hopefully it'll be fixed, though since S-E has let the bugs stand for a while now, I'm not particularly optimistic about them releasing a patch.