So, instead of going for the emotional argument, let's look at why there is a problem.
I know a couple of hikers who have no desire to use anything but modern sanitation facilities. They only do dayhikes up Whitney. So in general, they are not the problem.
If someone is willing to eliminate/defecate/take a dump outdoors, it really isn't any different to dig a cat hole or get it into the green bag. So that's not the problem.
The problem is in carrying the package up and down the trail with the associated stench trail. Who really wants to be hiking 10 feet behind the guy in the backwash of his dangling poop bag? Not me.
So what's the solution. I love win/win, two birds with one stone solutions.
There's also a shortage of overnight permits. At least from my perspective, since I didn't get one this year.
How about two permits being reserved every day for walk in wag bag haul persons (one for outpost and one for trail). The Designated Poo Hauler sets up a drop point and they collect during the day while the DPH is hiking to the top (sans poo). Then the DPH picks up the accumulated packages and brings them on down the hill. I hike alone, so I wouldn't have to worry about a hiking buddy swimming in the backwash.
Another way to handle it is like an aluminum can deposit. Everybody puts down $5 with their registration. If they return a full wagbag, they get their deposit back. Sure, a lot of people will blow off a five dollar deposit and leave their wagbag up on the hill to avoid carrying it. But there are going to be people who think "hmm, 20 bags is $100. I'm willing to carry a bag of poo for a couple of miles downhill for $100."
I know, I know, it won't work.....but what we have now doesn't work. Maybe providing incentive to some hikers who can gain something by the removal of wagbags can benefit everyone.