Yeah it was fun in the beginning, after all who never thought about being transported to another world where you ate a big hero with swords and magic?
But what the hell, I'm pretty sure there's more isekai now than other genres/settings. It's gotten to a point that if I see the tag I just move on.
Disclaimer: Coming here from all, so I might not be the audience you're looking for.
I don't tend to just browse for new releases that might be neat, but I've noticed this from the outside as well. Just through the stuff I run into under reccomendations on streaming services and sites. There's a ton of anime coming out that's either isekai, harem, power fantasy, or a combination of those themes.
I think there's potential for some really good shows within those areas, but like most media, I feel that you're more likely to find quality by stepping back a bit and waiting to see what holds up over time.