In a nutshell the Internet and possibly the child sex abuse cases that are getting more media attention now ,that`s whats destroying (?) the WT/JW religion though it`s going to take a far longer time than most people would like.
"Destroying" is probably not the best terminology to describe their demise .It`s going to be a gradual thing over a long period of time which means they could still be around many,many years into the future , however with a much smaller membership than they have now.
As your OP suggests most/many JW`s accept shunning and are quite willing to abide by the GB`s directives to enforce it even when close blood Kin are involved .