I'm talking from first hand experience as I have attended numerous non-denominational services, while at the same time remaining in contact with my Catholic roots. I can tell you there are several non-denoms in my neck of the woods that are truly thriving.  I highly doubt that you have this perspective so your argument is based on hearsay at best.

My assertion that the RCC may follow suit is also based on experience (and reality).  As in this very article, what in essence will result from a consolidation of several parishes into one large one?  You guessed it -- a large conglomerate of sorts fashioned after the Protestant "megachurch." A decline only happens when and where church leaders fail to live up to gospel standards... educated masses simply do not well tolerate false piety and/or hypocrisy.