Rental-car reality
If you drive the Cottonwoods, legal is not the same thing as good
Utah's canyon traction rules are unusually specific.
When restrictions are active, every tire must have at least 5/32-inch tread. AWD and 4WD vehicles need qualifying M+S or 3PMSF tires on all wheels, or approved traction equipment. Two-wheel-drive requirements are stricter.
Meeting the rule should not be the end of the conversation. M+S is a broad minimum. It does not tell you how a tire behaves on ice, fresh snow, slush or cold pavement.
Legal is not the same thing as good.
If I am taking a rental into the canyons, I want the actual tire make and model, winter rating, tread condition, drivetrain and a clear answer about permitted traction devices.
That is why an exact-vehicle rental can be attractive for a ski trip. You can ask the owner what is actually mounted before booking instead of discovering it under fluorescent rental-garage lighting while everyone else is already loading the bags.
Conventional rentals can work too. The point is to know what you are getting before the canyon checkpoint, not after the storm has started.