On the spectrum of how companies and governments handle private data, they're pretty good actually. Just, the bar is so low you're going to need an archeologist to dig it out; Not hard to far exceed said bar when you can just stand at ground level.
But most fundamentally I am against them because they're an advertising company first and foremost, and if there's one thing I trust them to do is to stay an advertising company. That means that without laws that have actual teeth to prevent misuse of data, they're always just a few decisions away from not being such good stewards of that data.
I'm not singling Google out much here though. My opinion would be the same with Meta, Apple, Microsoft..etc. I don't hate Google, I hate the whole damned system.