Honestly Arch-based is a good choice, but straight up Arch for a newbie? Nah.
I’m running EndeavorOS with KDE and it’s been solid for gaming. A few bugs, but mostly minor, like it picked the wrong default NIC driver (but still worked) and SMB shares wouldn’t auto mount recently until an update a week or two ago.
My main PC for non-gaming runs Manjaro. I know there are haters about it, but it’s been a solid distro for general use, and I’ve encountered no issues to speak of.
I mean, it should be fine, just because the PSU can provide more watts doesn’t mean the system is actually using that much power. I have an 800w PSU in my gaming rig, but its average load is only 240 - 320w during gaming (I’ve measured it by powering the system with a portable Ecoflow battery).