Is this not up for debate either? Because I wouldn't enjoy a game more or less if it went from 30fps to 60fps, it wouldn't affect how much I enjoy the game whatsoever, 30fps is completely fine with me, and if I enjoy it with that, yes, I'll enjoy it at 60fps but not because of the framerate increase. Likewise if a 60fps game played at 30fps I wouldn't find it less fun whatsoever, it wouldn't affect me in the slightest.
However, keeping on topic of what I'd actually sacrifice in order to reach 60fps, I'd drop the resolution and reduce the effects, maybe texture resolution, but only if the art style of the game would allow it, by which I mean only if the game has an art style that wouldn't necessarily be compromised and ugly to look at as a trade off for the increase.
Framerate is not like game design (though the two often clash, and are forced to co-exist).
A terrible game at 60 FPS is still a bad game.
Even the most framerate oblivious people would still find the lower response time, smoothness and overall "feeling" provided by 60FPS to be better than 30.
Even when we don't have the tools to express or understand why is happening 60 FPS is more enjoyable.
A better designed game at 30 FPS will most likely be more enjoyable to play than a poorly designed 60 FPS title though, but more in the way that makes you cry out in praise: "Gee I sure am having fun".
Doom (2016) will run at 30 FPS on the Switch, and people surely will enjoy it in that incarnation, they are not wrong to do so.
They may find it more enjoyable than playing it at 4k240 on a monster PC, be that due to: the Switch logo, portability or some other reason.
Given a 60FPS version on the Switch, with the same graphical fidelity, they will enjoy themselves more, even if they don't know it, or understand the difference.
At that point it is more of a subconscious thing.
Think of it like this: lip sync in movies, you can still watch a movie with a half second (or in 30 vs 60 FPS, ~ 16.7ms) audio delay, and hell you personally may not even be able to discern a difference, but at some non active level your brain will be able to tell the difference.
I am sorry but it is not up for debate, but that does not mean you are wrong for being okay with 30 FPS.
It is a topic that is hard to talk about without stepping on feet, so I am sorry if I have offended you in any way.
There goes VGC ruining my formatting... sigh.