Look at that fucking wolf 
From what I can see it's the original level geometry with upscaled textures and some very unevenly updated models. In the middle screenshot the shotgun on Lara's back looks like the original square PS1 model while the handguns have been remodeled. The end result looks like Minecraft with one of those high res texture packs
Lara herself looks like she's from a 2006 game while I have no fucking clue what's going on with the wolf, it looks like some bizarre attempt at remaking the model while keeping the PS1 art style or something
Edit: The announcement on Steam is pure quality:
Tomb Raider I-III Remasters Launching Feb. 14,
2023
The remasters include all Expansions, secret levels, and updated graphics!
Lara Croft is back!
Aspyr and Crystal Dynamics have partnered to announce Tomb Raider I-III Remastered Starring Lara Croft, a new three-game bundle of the first three Tomb Raider titles (Tomb Raider, Tomb Raider II, Tomb Raider III), lovingly restored with upgraded graphics and performance enhancements, complete with all expansions and secret levels.
Available Feb. 14,
2024.
If they're not available until February of next year then a lot of the models and textures could be changed or updated by then. Not entirely related but I couldn't stand the newer Tomb Raider games. I could only play for 15 minutes at a time before I got bored. Reminded me a lot of Max Payne 3 where it just dragged on and on and on, just the same repetitive shootouts in a way I never felt with the first two Max Payne games. Couldn't even care about the story because as soon as I'd be surprised that a character double crossed me it'd turn out they actually triple double crossed me, and oh now they're dead so who cares. Who was that guy again? Oh well, on to the next set piece. I swear there was a whole Era of AAA games that were boring as fuck.
There was very little old school Tomb Raider puzzle platforming left in the reboot, it was just Triple A Action Game: The Game, though it was decent at being that