"...purely for altruistic reasons and for the sake of engagement."
Frankly, I am uninterested in interaction otherwise motivated. Why would I care about content that is only posted to earn money? Am I a cow producing that sweet, sweet milk?
No, I am not.
Well, this is how Steem / SCOT work. Based on a reward pool that is distributed, among others, to those who are upvoted for their engagement. So in a way the intent of the engagement is a little blurry, except in obvious cases. Even some good engagement may drop, if there is no reward involved.
On Steem, maybe this is not wanted anymore, going forward. Possibly the STEEM / SP rewards will be replaced in time by SMT rewards, so maybe HF21 is only the beginning that prepares the terrain for what's next.