I've also been commenting a lot over the past decade. Partly for practicing my writing, like OP, partly to help maintain balance within the social order by shedding light on alternative perspectives which were often overlooked.

But now as my comments are likely being fed into AI for training for profit by specific individuals, it doesn't feel the same. I'm getting a stronger urge to keep my expertise to myself.

Also, the benefits of good writing aren't as great anymore. I still kind of benefit in terms of practicing my tough typing... It's valuable to be able to type AI prompts quickly.