Do you enjoy a provider who talks dirty during the session, or moaning?

Dirty Talk can be both arousing and distracting and difficult for providers to hit the target on.

If it’s subtle and timed right with just a little touch of sincerity that I’m ok.
The fake shit she can save it for someone who’s into it.

If the dirty talk and/or moaning seems natural, not forced (“Let’s see, I’d better moan now to make him think I’m enjoying whatever the fuck he thinks he’s doing”), then yes.  If the provider is just acting but graduated Summa Cum Laude from the Acting School for Sex Workers, that could work too.

talking as the province of those less-educated people with a limited vocabulary, so when people that fit this description do it, it seems perfectly natural and entertaining, but when those that don't normally talk that way do it, it comes off as contrived and exaggerated, and is more of a turn-off than a turn-on.  

Dirty talk often feels fake and distracting, not at all arousing.  

the woman I know who’s one of the smartest vocabulists I know, author of a few books, great conversationalist, and is also a freak in bed who loves taking dirty, just because it’s fun for her.  When she does it, it’s a turn-on.

It’s the modulation that’s key.
I remember a lady I saw a few times whose main articulation was a few genuine sounding sighs of pleasure, an encouraging moan now and then, and once during doggie she turned her head, looked me in the eye and said softly but passionately  “fuck me”. I came a nanosecond later.

and vocabulary level.....But it's how you think so...

A poor actor does not sully the source material, they sully themselves.

I will be 44 this year, so I’m to old to fake it. No need to act. I love talking dirty & do so even when I am in private pleasing myself. I find it very arousing.

Not over the top. 1 second into daty and shes screaming? Cmon man.

You're just that good!
: )

They are just in a hurry to get it over with.

If sincere and done well, it is magnificent.  It can't just be screaming a stream of expletives.  It has to seem organic and build with the (perceived) passion.