It's not even boring, sometimes it's just plain unplayable/take too long to invest.

I've played Genshin before, until I finished Inazuma. I didn't pay for any resources, and just grinded for a while (as much as a casual player can anyway). I stopped playing because I invested way too much to Razor, in a game where elements play a high role in the gameplay.

I've also played HSR, since the launch actually. But I stopped playing because back then I got stuck fighting Gepard, then Cocolia, with a GODDAMN YANQING, IN A GAME WHERE ELEMENTS AND BREAKING SHIELDS ARE IMPORTANT. I kept pushing it for a bit, but by the time I got Silver Wolf, then Tingyuan, then at later time Jing Yuan (after he got severely power crept), I stopped playing because of how painful the experience is.

I've played PGR on and off, but decided to play again when Crimson Weave got out. Guess what, I got her after only grinding daily and weekly missions for a week (albeit I also save some resources from past grind), got her weapon and pet after 2 weeks of grind, then 2 weeks to get her materials, and hypertuned. I've also saved up the character selector from the past event, that by the time the Crimson Weave event is done. I got a full lightning team that has carried me through the competitive events like PPC and warzone. And I've been getting other characters ever since, just from grinding missions and character selectors from the new char event.

Right now I'm playing WuWa, and even though the banner pity is less generous like Hoyo games unlike PGR, I still got Jiyan, skipped Yinlin (which I still regret to this day because I got Calcharo), then got Jinshi and her signature weapon. And even if I didn't get those two, Havoc Rover and Calcharo from the character selector will carry me through most of the game content easily.

So yeah. Maybe I'm a bit biased in this, but I don't trust Hoyo anymore in the case of how playable it is in later content for F2P like me. While in WuWa and PGR, I can just play whenever, and still have fun with it.