Did you agree with it before the AI wrote it though (in which case, what was the point of involving the AI)?

If you agree with it after seeing it, but wouldn't have thought to write it yourself, what reason is there to believe you wouldn't have found some other, contradictory AI output just as agreeable? Since one of the big objections to AI output is that they uncritically agree with nonsense from the user, scycophancy-squared is even more objectionable. It's worth taking the effort to avoid falling into this trap.

No, but this is different.

"I asked an $LLM and it said" is very different than "in my opinion".

Your opinion may be supported by any sources you want as long as it's a genuine opinion (yours), presumably something you can defend as it's your opinion.