No, Park City is fairly close to the vast complex of cities centered around SLC, but in the mountains to the East. It's the home of the Sundance Film Festival and ski areas. Upscale. I'm south, closer to Arizona.
I would venture to say the laws in Utah are a complete mess. The ebike dealers say it's OK to go on the multi-use paths, but the paths are signed "No Motors". There is a guy now, in an ATV, enforcing something, I don't know what. Basically they are bikes except when they aren't bikes, and the power limit is defined by the 1000 watts or 20mph limits.
It's curious about the 14.5 MPH speed limit. I can definitely see where people would go this route, just given the problems with speed on an MUP. They don't mention S-Pedelecs, they mention mopeds. The industry really loves the Pedelec concept, like it makes ebikes just like bikes.
I doubt Utah will follow California, with the 3 categories. They just don't follow California. The mess may remain until ebikes catch on.
People in this online community seem very comfortable with speed and relatively complete access to bike infrastructure. I'm not nearly as optimistic.
The Boulder thing is interesting. Colorado will let you on a bike path, but you can't use the motor. Boulder won't let you on the bike infrastructure with more than a 400 watt motor, I guess. This stuff really could take a nasty turn.
Ebike definition in Colorado follows the HR 727 National Law: 20 mph (30 km/h) e-power and 750 W (1 hp) max, 2 or 3 wheels, pedals that work. Legal low-powered ebikes are allowed on roads and bike lanes, and prohibited from using their motors on bike and pedestrian paths, unless overridden by local ordinance. The city of Boulder is the first to have done so, banning ebikes over 400W from bike lanes. (wikipedia)