Nice response from Petronia:

I think the problem is the assumption that if you don’t have the time/resources, you must not be “getting enough out of the intellectual conversation” (joy in discovery, etc.) to prioritize it over your current use of time/resources, and thus you can’t really be taking it seriously. Which, yes, can come across as pretty condescending. I don’t think it’s what Dave means, although it’s a standard way academics and un-/under-employed deep thinkers can condescend to the employed. :P Personally, I make no bones about it: I’m very scattered in my interests and have a remunerative and time-sucking day job. Nine times out of ten, I do deprioritize intellectual conversation because relatively speaking, there’s less in it for me than something else I could be doing. But I barely play a critic on the Internet, let alone am one - I’ve merely reached the point where I want to measure my non-fiction writing against pro standards rather than amateur ones. The only thing I feel bad about is leaving the other person(s) in the conversation hanging, not whether I’m taken seriously.