In my conversations with providers, they're also not concerned about age but about attitude, chemistry and new clients being HWP.
I don't think hygiene is a big concerned in North America, but it's not always for granted in Europe, Asia, etc.
I know an escort who has sensitive nipples and playing with him that way always gets him very horny. You'd be amazed about the number of clients who never even heard about nipple play and are surprised he enjoys that.