Well. WE say that age doesn't matter, but the question as originally posed had at least an inference of asking the question in "industry" terms. and there, I would say that there, yes, age does matter, or does/did at certain times. If Young Lions are what's hot, every label will have one, and everybody else can fend for themselves (and Woody Shaw gets dropped from Columbia...). If Elder Statesmen are in vouge, the same thing.
Now, afaic, age doesn't amtter, but life experience, "seasoning" if you will, does. If it's usually true that seasoning comes with age, it's by no means always so, And - a lot of players get comfortable and/or complacent as they age. There's no hard and fast rules.
But overall, I'd have to say that age/life experience/whatever matters more if you're trying to play a style that's older than you are. We got loads, TONS even, of young neo-hardboppers today who can play the notes perfectly, and even swing them with fire and conviction, but the "flavor", the little things that let you know that this isn't just "music", it's REAL LIFE told in REAL TIME, ain't there. I'm skeptical as to whether these cats will ever get that deeply personal touch, because it's the music of a time and place that's hardly existent any more, if at all. Eric Alexander, for instance, no matter how great he plays, will never have the flavor of George Coleman, simply because George's music is/was of his life and times, and Eric's take on it is that of a history student, a highly skilled and dedicated student, but not somebody who is playing about a life and time that is completely thier own, either.
That's not a dis on the abilities of cats like Alexander, nor is it calling into question their sincerity/dedication/etc. It's just to point out that there IS a difference, and if you're somebody who has an inclination to hear/feel music in those "life-specific" terms, you can't help but notice it. If you're not, then you probably won't (and shouldn't - there is much to be said about the non-superficial entertainment value.of ANY type of music played well and with professional integrety). Neither way is necessarily right or wrong. It's just worth noting that we all look for (and get) different things out of music, depending on our personal tastes and needs.