You have a good point here, but just from what I've seen with symphonies, it seems like usually the performers, of both sexes, are fairly young(-ish). And they

You have a good point here, but just from what I've seen with symphonies, it seems like usually the performers, of both sexes, are fairly young(-ish). And they're usually all reasonably attractive. They're up on a stage for people to see them, after all, so naturally whoever's trying to keep ticket sales up is going to want them to look nice.