Genshin Impact runs on the A9, I don't think there exist any more computationally demanding games on mobile.

What games are you referring to?

I enjoy xcom 2 and civilization for example.

Those run on the A9?

No. Both of them need A10 or newer and recommends minimum a11.

Genshin also needs a A10 as minimum.

It does run on the A9: https://www.reddit.com/r/Genshin_Impact/comments/j0jzxk/the_...

With low quality graphics admittedly, where you'd get this information?

What percentage of iOS users are really hardcore gamers? I don't know, but I doubt it's even close to 25%.

It's anecdotal but I don't know of any iOS/iPadOS user that plays anything remotely demanding. Most users I know don't game. Those that do usually play casual games like Candy Crush.