hmm, that's kinda funny cause I actually play lots of Genshin. But the system in practice works and feels very differently. (I also started working on this before Genshin released, and didn't know what a gacha was before I started playing that lol)
In Genshin, as F2P, you get 70-80 or so pulls per patch (6 weeks), but in my game, it should only take a few minutes to get an upgrade attempt in the late-game. And of course, you also get other resources like XP and loot for other stuff at the same time. Upgrades are only one part of progression, and you don't need to collect dozens of weapons in the late game, like you do with characters in gacha games.
Also, I'd never wanna sell power in a game I made, not that I think I'll ever get to a point to release this in the first place, it's just a hobby project :)
To give some more details, this isn't something that happens rarely, the chance of getting to the next checkpoint is actually quite low towards the highest upgrades. To get a weapon to max level (+15), it takes on average around 230 attempts (would be 280, but there's a sort of pity system that very slightly increases the chance of success for every failure on that weapon). Though it's also important to mention that this is something only really feasible in the mid to late game, and there's a mechanic to do multiple attempts at once. Technically, I could also make it so that there is no chance of failure, and instead drastically increase the amount of resources required for the upgrades. But I'm designing the resources needed around the average amount of upgrade attempts it takes.
The reason I'm doing it this way is a similar reason to why I enjoy farming bosses or special enemies in games like Borderlands, it's fun to get that rare drop (my game also has loot with rarities etc). So it's not that you're upgrading and rarely get unlucky and get a failure, but instead you're farming enemies to get the resources and try to get to the next level checkpoint on your weapon. In looter shooter games (or any loot-based RPGs), you kill bosses again and again to get a special drop, and all the attempts where you don't get it are technically a "waste". I think that, because failure is the expected outcome, it's not something the player gets surprised and annoyed by. Rather, it's the hunt for getting that success that's the focus.
I also remember playing older MMOs etc that had weapon breaking mechanics upon failure, but premium items that protected your weapon from breaking. Usually you could get some of those for free, but they were very limited, so those games always were quite P2W. But I did enjoy those systems, just hated the real money aspect.
China is also capitalist though, and they're also starting to suffer from the same issue.