This block of voters, the actual deplorables, now make up around 30 to 35 percent of the base.

Maybe more.

Donald didn't just NOW reveal himself (or was revealed to be) the asshole he really is, his supporters knew what they were getting when that voted for him over and over in the primaries.

If they cut them off, the republicans become a regional (south, some midwest, inter-mountain west) party which can NEVER hope to hold onto any branch of the federal government ever again.

if they want to really reform, this is their tool. their only tool.

You can cut off a limb and still survive. You can't cut out your vital organs. The GOP today doesn't compare to the DNC of the 60's. At that time the Democrats were big enough to concede the deplorables to the other side without disintegration of the party. The deplorables really have nowhere else to go outside of forming their own party anyway, so it's not as if they aren't going to continue to wield power over the GOP. So while the GOP could certainly try to silence the deplorables and reinvent itself, the problem they would inevitably have is the deplorables aren't going anywhere and they are still going to be driving off anyone who is sane. So all disenfranchising them would really do is continue to cut off whatever dwindling support they have left.

Major political parties do come and go. It just hasn't happened recently, but that doesn't mean it won't. I suspect the GOP will try and hold on to the House for a few more years thanks to gerrymandering, but if their fall is catastrophic that could even collapse.

They can't win in states without them.

not any more. they are not going to win anywhere anymore and for a lifetime.
they might as well try to rebuild w an honest base. a sane base.

The real motivation behind the GOP, at least for the last hundred years or so, is oligarchy. While the GOP could certainly try to be honest and say all they are really about is making the rich richer at the expense of everyone else, I just don't see that as a winning strategy.

So far their tactic has been to cobble together various special interests, most of which are described by HRC as the "basket of deplorables", but changing demographics is working against them which means that in order to retain power, they have to get an increasingly larger share from that basket. So the options the GOP realistically has for success is to either dissolve and become born again with a different ideology, or to completely abandon their current ideology. Either way the GOP as we know it today ceases to exist.