Rude and nasty? Nah... not even close - I save that for folks I dislike.
I suspect you could count on the fingers of one hand the "fluent" Turkish speakers on here, i.e. those who could be classified as Advanced (C1/C2 CEF scale). It's likely that there will be a higher proportion who are scattered between Beginner (A1) and Upper Intermediate (B2) with the bulk being A1/A2. Then of course there will be those who simply have their two weeks here and there who have no need (other than daily pleasantries) to learn any Turkish.
While not holding permanent residents in "contempt" (your word, not mine) if they don't speak any Turkish I do find it a bit disrespectful that so many make no effort whatsoever. Maybe its a British thing where everyone is expected to speak English, a throwback to the days of colonialism.
I know quite a few folks who live in Fethiye full time, have done for several years and speak next to zero Turkish. Not even numbers or days of the week.
I just don't get them.
Personally, I've never got beyond Intermediate (B1) and through lack of use I suspect now I'd be lucky to scrape past Elementary. International law firms in Turkey all use English as the common language so working for one didn't help my Turkish.
I had to go to Dundee for Turkish lessons, there were none in Aberdeen. Some of the Turkish people I know speak very little English so I enjoy being able to converse with them.
Did you go to Dundee Uni for lessons? If so you may have had the same teacher I had years ago, cheery wee chap called Oz.
JF