I completely agree with you, but as a ChatGPT user I have to admit my fault in this too.
I have always been annoyed by what I saw as shameless breaches of copyright of thousands of authors (and other individuals) in the training of these LLMs, and I've been wary of the data security/confidentiality of these tools from the start too - and not for no reason. Yet I find ChatGPT et al so utterly compelling and useful, that I poured my personal data[0] into these tools anyway.
I've always felt conflicted about this, but the utility just about outweighed my privacy and copyright concerns. So as angry as I am about this situation, I also have to accept some of the blame too. I knew this (or other leaks or unsanctioned use of my data) was possible down the line.
But it's a wake up call. I've done nothing with these tools which is even slightly nefarious, but I am today deleting all my historical data (not just from ChatGPT[1] but other hosted AI tools) and will completely reassess my approach of using them - likely with an acceleration of my plans to move to using local models as much as I can.
[0] I do heavily redact my data that goes into hosted LLMs, but there's still more private data in there about me than I'd like.
[1] Which I know is very much a "after the horse has bolted" situation...