This ‘I choose to be offended’ stuff is abdicating responsibility.
I think it can be, but not necessarily.
At it’s heart it’s largely true for simple cases. If someone described me as, oh I don’t know, “skinny” say; they could mean it perfectly innocently as a descriptive term, whereas I might be particularly sensitive about my weight and take offence. In that situation, the other person isn’t being offensive, I’m choosing to be offended. It’s the same sort of casual indignation so beloved of the Daily Mail readership, usually on behalf of someone else who they’ve never met.
The problem is that, whilst I believe that the statement “you choose to take offence” is largely true, it breaks under reductio ad absurdum. You couldn’t call me a mothereffing cee and then go “ah, yes, but you’re -choosing- to take offence.” Well, yes, I am, but that neatly sidesteps the fact that you’re also choosing to be offensive. Just because people “taking offence” is an action by the potential offendee doesn’t give the hard of thinking carte blanche to treat people like pondlife.
And, we’re back to context and intent again.