Another thing I like about highlighting stuff is that Medium saves a list of highlights so I can go back and find the direct quote later! (I wish they'd organize this list better, because if i'm looking for one particular sentence its hard to scroll through and find it.)
Do you happen to know (or have any guesses) as to how the algorithm interprets claps, comments, highlights, and comments-from-highlights?
I'd imagine that highlights and comments-from-highlights represent the highest levels of engagement. Claps are probably up there. Blind comments maybe last? Maybe blind comments still beat claps? What about replies to other people's comments?
I really like engaging with people on the comments of articles, so I hope these threads end up boosting the engagement metrics for the OP.