These are somewhat valid reasons, but I think most of us have seen the use of pasting AI responses that are simply a laziness of communicating.

If you're trying (1), it's easier to say "I don't know, maybe <available ai> can answer". It doesn't save any time to ask an AI that the other party is equally equipped to ask. It just saves the responder time from being genuinely helpful.

If you're (2), at least explain this (or include the prompt so it's self evident and a teaching moment). Of course, if you're a SME, maybe you also have the knowledge to just answer directly - see 4.

For (3), why reply at all: see 1.

For (4), saying this associates your own authority and knowledge, and is valuable, but the omission of such disclaimer makes it indistinguishable from 1.