and there is nothing in there about not waiting in the intersection while turning left:

Here are the simple rules for turning and an intersection.
https://le.utah.gov/xcode/Title41/Chapter6a/41-6a-S801.html#:~:text=Turning%20--%20Manner%20--%20Traffic-control%20devices.,-The%20operator%20of&text=Right%20turns%3A%20both%20a%20right,or%20edge%20of%20the%20roadway.
41-6a-801. Turning — Manner — Traffic-control devices.


There is this clause but it says that there has to be somewhere for you to go if you're going to enter an intersection.... e.g. if you enter it and the light turns red you have to have the ability to leave the intersection.
https://le.utah.gov/xcode/Title41/Chapter6A/41-6a-S1707.html?v=C41-6a-S1707_1800010118000101
41-6a-1707