I'm sure Pugski can correct me, but I understand skiing has a 10% return rate. In other words, only one in 10 newbies come back to do it again. Given skiing is the best recreational activity on earth that you do clothed in the outdoors, that's ridiculously low.
Frankly, I think the industry committed an enormous own goal when they talked rear entry boots into oblivion. Uncommitted recreational skiers couldn't care less whether their boots are the ultimate in performance, but for reasons that I'm sure are clear to someone the industry, they killed them off and in doing so made it that much harder to get uncommitted new skiers to return (because they complain ski boots are hard to put on and take off, uncomfortable to wear, and hard to walk in). WTR and Grip Walk dont make boots easier to put on or more comfortable, but they do make them easier to walk in.
So I think moves to make ski boots easier to walk in is a completely sensible path, removing one impediment to keeping the less committed skier in the sport/lifestyle.
I haven't used GripWalk but WTR is basically a half way house between Alpine soles and AT soles, with the safety of a normal Alpine sole, and I'm familiar with WTR. For all but the committed long tour AT skier I think Grip Walk is a sensible choice for expert skiers doing a bit of resort skiing, a bit of hiking and/or sidecountry, assuming it is similar to WTR (and I believe it is).
The transition to a new norm will always be painful. In any event, Alpine soles will continue, so it's not like old bindings will become obsolete. Some of them just can't be used with GW bindings.
I think long term GW (or WTR) is better for 90% if skiers.
I do have one pair of bindings which won't be able to be used with GW soles but that's a problem for when I get new boots, which will be at least 4-5 years away, minimum.