I agree entirely. But I think that people are sorely out of practice in discussing social issues in any meaningful way and need all of the practice that they can get. Obviously, trollies are people who speak from a dishonest rhetorical position, but this doesn’t prevent one from sharpening their skills (or claws) upon it. IMO honest engagement sets a better example for both the trolley and casual readers. Not unlike a debate club, it is still a good exercise even if people are not arguing for/against their real personal position.
And it can be entertaining to watch trollies either fail to go into further depth, or undertake credibility-defying measures in an attempt to excuse or persuade. In any case, I think that people inevitably learn something in the exchange. Unless people get mobbed or silenced. My personal policy is that people should be free to debate or discuss any views, so long as the discourse itself remains civil.
Ideas can be insidious! Sometimes they sneak in and nag at people. And even if it didn’t give them anything to think about, they weren’t the only one who read it. That’s why I think even topics and views we would probably agree are terrible deserve debate. Those values and ideas do not come from nowhere. Especially when the main authoritarian tactic is to discourage debate and make discourse meaningless, doing it anyway is the best resistance.