@pseudomonas @A_C_McGregor You're replying to Alisdair, but in my thread, so I'm gonna assume "you" means me.
The answer, in general, unfortunately is "no". Posts that I can reasonably expect are only going to DFRN or ActivityPub type places support abstract (which gets converted to content warnings for ActivityPub), but unless I specifically restrict distribution, posts go to other places which handle them very poorly.
Do feel free to mute the thread.