I've always liked older men but,
...now that I AM an older man, I prefer a guy my own age or younger but not too young.
The bottom line is what sells? Memberships on web sites are one thing, often affordable but, sales of DVD's, mags, etc. has always been left to those with plenty of disposable income the (50's-60's-up group). The youngsters don't have their careers off the ground yet and pretty much feel that they could pick up anything they want if they go looking for it.
A lot of older guys like youngish guys, reminds them of their youth and makes them think they must still be hot if they can get their hands on m' or
pay for m'...
Let's not forget the libido thing either, most young guys can stay hard for hours on end (and don't need help to keep it up). Great for performance stamina!
Personally, the general youngish under 25YO is a big turn off in our household. The skinny (Twiggy) mal nourished, often queenie, white fleshed, pimpled, baggy jean hanging around the ass look makes me wonder if we have returned to the 60's?!?!?!?!
However, couldn't turn down a young gymnast or swimmer with the right manly stuff and testosterone exploding from within! I was there and I often wish that I were 18 again - with the knowledge I've got now!