This very interesting question has an answer that relies on the dubious assumption that the frequency response of time-varying systems exists in continuous time.
I believe the answer is blatantly wrong and should not appear on the site and should be deleted. However, since I've been involved in the discussion in the comments there, I don't think it's up to me to do that.
I've given a specific example, but my general question is:
- Should plainly incorrect answers be deleted?
and as a follow up:
- What happens if they are the accepted answer?