I think there should be some incentive for that, like make those kinds of comments a spotlight or something. Maybe make a community called “late replies” that showcases the best such replies, or have a rule saying they grant free karma (in Reddit’s case).
April 18th.
If I see the person still active on the platform I’ll try my luck. Otherwise if it seems like they are the only ones on the whole internet who (possibly) knows how to help with my problem, but that’ll more likely result in a DM.