As the guide says, the speedrunning differences between launch and rev 1 are the time together 4 skip and faster cutscene skipping.

Well, are there any in-game improvements between the versions, such as graphics, performance, sound, or content? I didn't notice any while playing them, but there have to be major differences, considering rev 1 is 2.29GB while launch is 1.97GB.

to my knowledge there are exactly three on the surface, which is time together part 4 skip not working, the home button fmv skipping is different compared to rev 0, and put on your sunday clothes in welcome to earth part 1 is a completely different version of it.

internally its missing some debug leftover files that are on rev 0 and i think theres some localization files either gone or there for some reason, but other than that its all the same.

pal (which is rev 1) on real hardware is fine but if you emulate it on dolphin you get some graphic issues due to it running in pal50 mode and it looks like its even running faster but i think its placebo as making the speed lower, unsurprisingly, makes it run slower than real hardware. if you want to be fair you can put it to pal60 mode in the options, which fixes the graphics and makes the fps limit be at 60 (if it can hit that)