Those are both Nintendo, not merely ‘Japanese’. However you may feel about Nintendo’s legal proclivities, they are a longtime major player in the industry and, despite the gimmicky nature of the last few consoles, produce a very consistent, high quality with a brand perception in the ballpark of Disney. Those two things make them the default choice for any content-conscious parents or grandparents buying for kids, which has historically been the bulk of the market.
//edit: I guess that is half the explanation- the other half is the now large population of gamers with very warm, nostalgic feelings for Nintendo IP after the massive impact it had on their youth.
I started the ubuntu path on warty, was a distro vagrant after unity arrived, switched to debian a while which was and is fine, decided to give manjaro a shot and couldn’t stand it, but oh how that AUR made me swoon. Finally worked up the nerve to lose the training wheels and try just arch, got tired of the immense chore that it became and found EndeavourOS.
I cannot recommend endeavour highly enough. It’s exactly what I always wanted and as long as they don’t completely shit the bed somehow I doubt I’ll ever leave. I can’t speak to your hardware concerns, as I went full team red with common hardware for my last few builds because I knew they would have linux on them. The arch wiki is great. The forum exists. They have a plasma version.
The only games I have been unable to play are those that have shitty anti cheat software and the occasional very recent release, but those usually get resolved in a hurry. Genuinely no complaints.