Building an offense around fields would be frustrating. A good qb and offense can do multiple things. Fields struggles with screens, quick game, finding a hot in a spread formation. Hard to bootleg when all they are doing is trying to keep him in pocket. You need to be able to beat teams in multiple ways. You need to deal from the pocket.
I actually don’t hate this but you would probably need a strong front office and reputable head coach to pull off a move like this. There was no noise in KC when they essentially did this. Alex Smith was a pro and they had him play one more year and then moved on.