If inornate churches that look more like strip malls and expo centers are so much better for the laity then imagine how much more good it would do for the top brass, relieving them of the burden of having to look at all that sacred art all day long. What's good for the goose is good for the gander.
It's hard to imagine the Catholic church being as prominent in the world as it once was, of course, but as member myself, the last couple of years give me hope that we might again start growing.
Of course it only adds to the decline when the hierarchy builds as if going to Mass is no different from a trip to the mall or seeing a show.
There’s also the hypothesis that if the Church gets prestigious awards for their avant-garde architecture people will finally start liking the Church again.