Honestly, I'm torn.
Yes, the gacha shit does suck, but the rewards are only cosmetics, and they make sure that it doesn't give you repeats.
I've seen fangames with far worse monetization. Remember Total Roblox Drama, that had entire characters locked behind a paywall?
Now reddit might call me a "Spike Chunsoft bootlicker" but I think that maybe a GMod fangame shouldn't be allowed to do this.