Anyone can still stand in line at Universal to ride.
(yes and anyone can eat at Disney with the idea I was giving they may just have to wait or commit by buying the DDP by making the DDP available to offsite guest) With your proposed policy, locals could be shut out of restaurants they're interested in, regardless of how far ahead they were willing to commit. Why do you think TIW came about? It's to get locals to spend their dining $$$ there, instead of the many other options they have available to them. If they can't get into the restaurant they want, why would they bother eating at WDW at all?
(Do locals not go to Universal too and deal with their restrictive policy?) TIW is also available to AP holders many of which have DVC.
(We have an AP and are not locals and are DVC and they are getting ready to sell the TIW to DVC members not just AP and locals, or so I have heard.) That 20% discount could be the difference in them eating in a WDW restaurant or cooking in their villa. If they can't eat where they want, they may decide cooking or eating offsite is the way to go. Then there's many others who don't use DDP or TIW that would possibly be looking elsewhere, if they had to accept what would basically be the leftovers.
If you're looking at it as a way for WDW to benefit, the current policy accomplishes that. They either get the money from the meal,
(they got my money when We bought the Dining plan) or they get the fee for those who make ADRs, then didn't cancel in time. Many people, who are also making ADRs under the new policy, don't have a problem with it. I'm sure the powers that be expect people to eventually accept it as normal. After all, they've convinced us that making ADRs 180 days in advance is normal. They also know first time guests, of which they put a high priority on, won't know anything different. If things don't work out as planned, they'll probably make changes. Whatever decision they make will undoubtedly be the one that they benefit most from. This is no different than any other business.
I do agree that they need to work out the bugs in the system. I'm just not really worried about unwarranted charges. Those will eventually be reversed.