As opposed to?
Do you really think OpenAI, Anthropic or any other entity in the same business respects your data?
The Chinese AI companies who release open weights actually deserve whatever input you give them. They are the reason why there is competition and not duopolies in the domain.
I think Google, and likely Anthropic, indeed do honor the settings chosen by the user. For Google in particular it'd be very surprising if they didn't. That's also why both do everything they can to trick users into allowing it.
OpenAI, I wouldn't be surprised if you were right.
unfortunately the history of these big tech companies has shown that they do not care about data privacy and are even willing to lie about it. but I guess its irrelevant, in practice you have to assume the worst anyway since there is no way to verify it
The models doesn’t get better by themselves. You’re naive.