So Post News is the first post-Twitter #SocialMedia casualty, but it won't be the last. I think it's clear that in terms of for profit microblogging, Twitter and Threads are going to be the ones to survive (I have zero confidence in the long term viability of such services as Cohost, Hive Social, Spoutible, and even Blue Sky). While I realize that #Mastodon and the #Fediverse aren't free, they aren't beholden to same market forces as the others and I feel they will continue to endure.
