Much depends on what is considered "fun" and "playfulness". When I was a late teen / in my 20s, people my age typically enjoyed getting drunk and partying, and I felt that was not fun at all. I still wouldn't consider a party-girl that age for anything serious, because they are not serious about relationships and only want to experiment. Thus, for an ND guy that wants a serious relationship, those girls are simply no good, no matter how playful they appear to be. Girls in their 30s are more serious, and this shows by their desires to get babies, which is not all bad, because it is evidence that they will commit to something serious.
About the playfulness, I'd say it's more related to neurotype than to age. ND girls in their 30s can be really advanced game-players, and take the whole thing to a completely different level than younger one's. That's because they are more mature and have more experience.
Still, I'd say very few women 40+ are playful. The few I know are easy to count. Even worse, most of the one's that are single are not relationship material either, because if they were, they would be in an LTR already. Rather, many are players in the bad sense that they won't commit to anything.