It depends on what you think Programmers.SE is for.
If it's a site for expert programmers who are interested in conceptual questions on software developmentexpert programmers who are interested in conceptual questions on software development, then answers had better be backed up by references. Even for the kind of subjective questions that make up the meat of the site, some kind of justification should be provided — real experts don't just say “yes” or “no”, they can explain why.
If Programmers.SE is Stack Overflow's toilet bowl, then answers aren't for reading, you don't know where they've been (or rather you do!), so who cares.