When I brought this up several years ago, the feedback was basically that “this type of thing will bloat the chain and is better off-chain”. I agree though (which is also why I brought it up) that using a centralized service isn’t idle and just leaves open the door for problems.

My question is, is there a way to have things on chain that don’t last forever? Say 2-3 months? I have never heard of anything like this, but I don’t see why we couldn’t think outside the box to make this happen.

For example, could chat get a special format which I will just call “json chat” that node replays don’t incorporate if the block is older than 3 months?

Or could chat be a parallel sister chain that is confirmed by the same witnesses but that only goes back X number of blocks.

I am just making stuff up, but I bet this could be solved.