It depends that 30 FPS game is going to LOOK significantly worse in motion than the 60 FPS game. However in static shots (like screenshots) the 30 FPS game will look better than the 60 FPS game. In fast motion the 60 FPS game will look far higher resolution than the 30 FPS game if both are at the same resolution. In fast motion a 60 FPS game will keep more detail than the 30 FPS game. All this assuming you have a good display with fast pixel response that can display 60 FPS without significant ghosting.
That said, if the majority of games you play are 30 FPS then that is what you are used to and what you think looks good.
Similar to how some people prefer "filmic" 24 FPS movies versus a more realistic 60 FPS movie or video because that's what they grew up watching in theaters.
After not having gone to a theater in over 5 years, I recently went to one and couldn't believe how bad 24 FPS film actually looks. It's truly a horrifying experience, IMO. Like watching a slide show, and motion resolution is the pits making the whole thing look far lower resolution than it is.
So the roles for me have been reversed. 24/30 FPS video/movies look weird and offputting while 60 FPS video/movies look normal which is contrary to how many people feel 24/30 looks more normal while 60 FPS video looks weird. That's due to the fact that since I don't watch 24/30 FPS content for a large chunk of the day (don't watch TV or movies generally), I don't have something that is extremely far from reality warping what I think is how things should look. While 60 FPS still isn't as smooth (still noticeable judder and stutter, just not nearly as bad as 30 FPS) as real vision, it's certainly a much closer match.
Regards,
SB