On Android it is kind of fragmented (big surprise) but here are some strategies to filter a lot of the mobile monetization:
1) Play Pass - 1000+ Games/Apps with no ads or in-app purchases for $5/month or $2.50/month when bought yearly.
2) In the Play Store, Filter by Top Paid. Most Gacha games are free to play to get you in the door so immediately the Top Paid section has some great games like Minecraft, Bloons TD 6, Stardew Valley, Don't Starve, etc.
3) Open the "Play Games" app and scroll to the very bottom of the Home page where there should be a "Dive deeper" section. That section has a number of filters, notably including "Premium", "No Ads" and "No in-app Purchases". It only shows title cards before tapping so browsing it kind of sucks but at least you know you've gotten rid of the stuff you definitely don't want. It also has a "Trending" filter so you can see newer stuff as it comes out.