Apologies, late to this party... been around SE for quite a few years but only just picked this up. I know things have now moved on and "identify" questions have now been made off-topic; I think the conversation needs to continue though, as this is still a young site with not much meta engagement yet from the community and such questions are clearly so very popular!
If these questions are off-topic on a site called Music Fans, where are they on-topic?
As evidenced by the existence of pop quizzes and suchlike, people love to think back on earlier music and try to recollect details about it. It's all part of the way music fits into life alongside human emotions, nostalgia and everything else.
If questions are low-quality, let's address that in its own right, not use it as a reason to deprecate one category of question or another.
On the stats Aaron provided, with the greatest respect to Aaron I think we must be careful about the conclusions we draw. For example, the significance of having only one answer. Unlike, say, many Stack Overflow questions, which are likely to generate a range of good and bad and misleading and mediocre and brilliant answers, an identify question has only one right answer. I don't think we should see this as being somehow of lower value than having multiple answers. And does the ratio of identify/not questions really mean the not questions are somehow being forced out? It's not like the "question bucket" is too full of identify questions, leaving no room for anything else. Will people not always simply ask the questions they want to ask? Doesn't the prevalence of identify questions merely show that that's what most people actually want to ask about?
Disincentivization has been cited, but that works both ways: I personally really enjoy "identify" questions. I haven't asked one here myself (yet) but I was delighted to find them here when I discovered Music Fans recently. I now actively search for them and enjoy pondering over what the piece in question might be. I am mortified by the off-topic decision and for me personally, it's a very strong disincentive to Music Fans because all my other musical interests are met by SE Music Theory & Practice. More than that, it's a great loss to the community because what other site exists to meet the obvious need for identify questions, which so many music fans love to ask?
Cue a new SE site, "Music Fans Identify"....?