Are 8-game pro sets and “4-game set” matches used for UTR Ratings?

Yes. 8-game pro sets and 4-game mini sets count for rating calculations, but receive slightly less weight relative to best-of-3 set matches.

Understanding the Algorithm - Complete Summary
What is a Universal Tennis Rating (UTR Rating)? Why should I have one?
How is the Universal Tennis Rating (UTR Rating) calculated?
What's the best way to improve my Universal Tennis Rating (UTR Rating)?
What is the impact of playing against opponents rated higher or lower than I am?
I had some great results added to my profile but why didn't my rating go up?
Why did my rating change when I haven't played recently?
What are the factors when a match does not count towards my Universal Tennis Rating (UTR Rating)?
Why does the algorithm exclude matches with a Universal Tennis Rating (UTR Rating) difference of more than 2.00?
What is the projected Universal Tennis Rating (UTR Rating)? How many matches does it take to go from a projected to a reliable UTR Rating?