Yes, but hard core fans are just there anyway. You're not going to change what the regular punters think after years of the hyped up Premiership. What the FA Cup needs to do is tap into the general national audience, the vast majority of whom don't watch games on TV at all. If the FA Cup (like international tournaments) was shaped as a national event via a national broadcaster, it would have its best chance of recovering some lustre.
Well.... I don't really know what such a change would actually achieve. It would just mean bigger but less interested tv audiences. Is the idea that teams would be sent out with extra purpose out of some sense of duty?
I mean, if I had a product I wanted to restore lustre to, probably the last thing I'd do is to give it away for free to as many people as possible.