Using X/Twitter to catch up and interact with the numerous friends, artists, and other communities there doesn't mean you support wage theft and withholding severance. It's hard to break away from such a populated platform, especially if most of the people you care about go to different platforms or don't share the same motivation to move.
I imagine GP is not only using 'support' to mean 'condone'; GP is using 'support' in its more literal sense, i.e. the users of the platform provide the means for the behaviour to continue by funding the company.
Because we should strive to improve discussions and pull them up to a higher level if possible. Especially on HN, where the comment section is actually useful instead of a cesspool of empty arguments and insults.
But saying "This line is a low-effort, cliché dismissal that does not engage the statement in a meaningful way" does none of the things you're hoping for, either.
If I downvote a comment, how is the author to know why? If I want to promote thoughtful discussion on HN, downvoting without explaining why does absolutely nothing to serve that goal.