PC https://youtu.be/Xl3H5pVeo4Q?t=215 - It seems to be twice as fast as on PSX. I would say that it should run at 30fps.
Your timecodes are wrong (the second video starts too late), but yeah, I've always thought that 60fps was wrong. In every video I can find of the original (whether epsxe, the official ps1 support on ps3, etc.), the swirl clearly takes about the same amount of time as the sound effect that goes with it. In the PC version at 60fps, the swirl is done and the battle scene is already displaying by the time the sound is over. Not to mention it just feels so... sudden and abrupt at 60fps.
Of course, 30fps YouTube videos are not really a good source for determining what's correct, in such a case. While it seems pretty clear that it's meant to be slower than 60, we would really need a 60fps capture of the original game running on an actual PS1, and we'd need to examine the swirl in that capture frame-by-frame to see how it's timed. If frames appear duplicated once each in a 60fps capture, then the effect can be safely assumed to run at 30fps. If they appear duplicated three times each, then 15fps, etc.