Is there any difference between Answermug banning or suspending members for what they post and Facebook, Twitter et al doing it to people?

No difference.  They are private entities and have a right to set their rules and regulations.  They also have the right to enforce or refrain from enforcing any comments they deem against TOS.  

 

  Well, semantically speaking, the mere fact that the same word is used is an indication that in at least one aspect alone there is similarly. Other similarities exist too. The difference, and/or differences, abound in many arguable ways, so the answer is a wash. It is different and it is the sane same thing. 

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This post was edited by Randy D at January 10, 2021 8:48 PM MST

I wouldn't know...AM is my only social media.

Yes. AM does not ban/moderate users based on their opinions. 
Just on 3 basic rules. 

1. Respect other users. 
2. Keep main areas clean. (No cussing, no obsene content, no hate speech) 
3. Nothing illegal
(Can view rules by clicking TOS at bottom of page) 

Big tech censors based on opinions of users.