I think it only really matters for gamers, but seriously, who's gaming on an iPad?! Use a PC or console!
I don't know how "mobile" gamers are using iPads (or tablets), but considering the size of the market, I doubt it's particularly niche.
I thought that basically fits the definition of "gamer" so I'm clearly mistaken. How do you define "gamer"? Someone who "always" plays games? (for some definition of "always"?)
Regardless, non "gamer" game players can still benefit from higher refresh rate screens, and they're not insignificant in number.
Mobile gacha/micro-transaction games often encourage frequent/repetitive play (e.g. via dailies, limited time quests etc). Would someone engaging in this likely consider the game to be a hobby?