Fascinating perspective, however, this "grandfathering" provision is nowhere to be found in the Constitution or B.O.R. Instead the 1st Amendment clearly protects the people or states from a federal establishment of "religion," which is properly understood to mean a christian denomination. The founders were christians overwhelmingly, but not all the same denomination. Thus general christian observances shared by all denoms was "tolerated"--Bible reading/training, prayer, posting of 10 commandments, ... (I'm sure some will point out exceptions, but these are exceptions.) These didn't become "unconstitutional" until the 1950's and following. Curious.
I admit that I do not know much about the history of Utah statehood.
Granted, there's a lot of hype saying that all of those things are now "unconstitutional", but none of them really are, unless they actually deprive someone else of life, liberty, or property.