Indeed, the vast majority on any social media platform does not engage. And when they do it's mostly just liking content and not even replying. You see it on lemmy as well, with news articles often having few comments. And when they do it's one or two top comments and a bunch of replies.
Over the years the only thing I can imagine is to add another anonymizing layer, where people can send in questions and the "best ones" are posted by a general/bot account. But that is something people much smarter than me have tried to figure out for years, so I have no idea how it would be implemented.
It's literally just a game to them.