That was exactly my point. Blocking instances because “that way my content can’t be seen there” doesn’t make sense, because it’s trivial to bypass it. Yes, even a screenshot will do the job if nothing else, so why talk about protocols in the first place?
Somebody (maybe you maybe not, can’t check while replying) said that blocking instances was useful so that “my content doesn’t get seen / shared / pushed / etc to people and instances I don’t want”. That doesn’t make sense because of the line above. If you need clarification on who are those people and what are those instances ask them, not me.
I hope I’m somehow conveying my message. If there is a subtlety in the subject that I didn’t catch feel free to help me understand.