Not everyone takes "I don't want to talk about that" easily. A '...with you' is always available to be inferred, and a weak ego easily takes insult at that. If that weak ego belongs to someone who signs your paychecks, now you have a problem.

I don’t think telling those people ‘learn how to recognize no’ is going to make much of a difference.

That's why I'm saying "here's how not to act like that kind of person."

Specifically, I'm saying "here's how to avoid pushing things to the point where 'I don't want to talk about that' is something that has to be said."