This is understandable, but I'm sure all the HN comments have been a part of training dataset for many chatbots now. In fact, this is a gold mine of sane and valuable sanctuary of comments, so this must have been definitely helpful.
I think the "ick" factor for me comes from the feeling that social engagement shouldn't really be queryable. When I participate here, it's an in-the-moment thing. While I realize my opinions are stored forever and searchable, and I generally stand by most of what I say, I think making meta-products around social engagement changes the flavor and the feeling of how we interact. It's like when someone points a camera at you. Sure, it doesn't really change anything, but also, it completely changes things right?
Be that as it may, I don’t think “everyone does it” is an excuse. An absurdly high number of people throw trash on the floor. I actively pick it up or at a minimum don’t contribute to the problem.
The answer to “many companies are unethically gathering your data” is not “it’s OK for me to be unethical too”.