I've informally started doing a thing where, whenever I zap a post with no comments, I leave one. The logic is that if there's a comment, maybe someone will pay more attention to the post, which I zapped because I think it's worthy of attention. I try to be thoughtful, bc what's the point otherwise? but if it were explicitly incentivized (vs implicitly) I worry that there might be an avalanche of worthless "first!" comments. So you'd wind up doing more harm than good.

This is what always stops me when I get uppity about wanting some reward for link posts that have textual descriptions.

I think it is a good idea. In some way it already happens with the comments being zapped more if they are good and early because they may get more views. A top comment after a day or two may not be viewed much so it gets less zaps even if the comment is great too.