First they aren’t “seething”, they’re not even that surprised, they’re just pointing out that the loopy billionaire was insincere the entire time.
It’s simply news when a famous person does the exact opposite of what they’ve been loudly pretending to champion for years. Man bites dog.
No. It is 100% A-OK for Ol' Muskie to ban who he wants for whatever spurious reasons he wants to post-hoc claim. It's his company, he can do that. 100%.
What people are correctly pointing out is that he rode in on his "FREE SPEECH IS GOOD" horse waving a "BOTS ARE BAD" banner, loudly proclaiming that "Only illegal speech will be banned", re-enabled a whole bunch of accounts for bigots based on bot-ridden unreliable polls, swerved hard to the alt-right lane, picked up a transphobic smoothie and blew both his feet off with a +100 Shotgun Of Hypocrisy by starting to ban people who mock, track, or report on him.
It's abundantly clear from his actions and inactions what is important to him, we have millennia of written history on these cases. At this point people are willfully ignoring it.