The libertarian maximalist i-can-do-what-i-want-with-my-computer ignore the many use cases where I want to trust something about someone else's computer, and trusted computing enables those use cases.
How is it great? Vanguard is extremely invasive; having kernel access, you have to relinquish your PC to this chinese-owned company at all times (whether you're playing the game or not), and just trust in their good faith.
And for what? Cheaters are more rampant than ever, now that they have moved to DMA type cheats, which can't (and never will) be detected by Vanguard.
So you give away complete control of your PC to play a game with as many cheaters as any other game. I wouldn't call that "great".
Now, the amount of DMA cheaters may still be unacceptably high, but that’s a different statement than “the same amount as”.
So, it’s not “giving up something for nothing”, it’s giving up something for something, whether that something is adequate for the trade offs required will of course be subjective.
You're right, a game with no anti-cheat or a bad one will have more cheaters. But as you said, it's about the tradeoff, and that's what isn't "great". It was for a period of two years or so, since the tradeoff was "lose all control of your PC by installing a rootkit, play a game completely free of cheats", which was compelling, but now that the game isn't sterile anymore it's hardly worth it, at least for me.
We gave up something real. But it has not been proven whether we got anything. Maybe we got nothing, maybe we stopped a few of the laziest cheaters, but we still see tons of cheaters. The number of possible cheaters is based off the quality of the software. No amount of aftermarket software will magically improve the quality of your game in a way that 100% deters cheaters. I’m positive that their marketing claims they reduce cheaters by an order of magnitude, but I have not observed them successfully catching cheaters with these tools.
I don't really buy the gaming one, in every other domain where a community of people are gathering to do a thing they enjoy together it's on the community and not the tool maker to figure out how to avoid bad behavior. If you don't wanna play with cheaters then just play with somebody else.
Relying on the community to police cheaters is not an effective strategy for online skill-based matchmaking games. There's a reason game companies spend money and effort on anti-cheat and it's not because they're ignoring cheaper alternatives.