IMO, it's a sign of the times.
People have shown an increasing desire to pre-plan
Disney vacations in order to get their money's worth. Guidebooks like Passporter and the Unofficial Guide...websites like TouringPlans which will map out your entire day...websites like this where guests share tips and tricks.
My wife and I spent most of our honeymoon at WDW about 15 years ago and we were completely lost. Didn't see a fraction of what was available. I believe we ate exactly one Table Service meal at a Disney restaurant the entire week.
A few years later we started making regular trips with our kids. For the first half-dozen stays I would plan out every detail: where to spend each day, restaurant visits and even the order for visiting attractions. When you're spending $3-4k for a trip, you want to get your money's worth.
Now for the typical visit I'll schedule a couple ADRs and map out some recommended days to visit each park based upon operating hours, nighttime shows (often to avoid), etc. But all of that is flexible.
Still, I think that approach probably leaves me in the minority. Many guests are ready, willing and able to plan 6 months in advance. Those who choose to wait risk suffering the consequences.
Does an ADR no-show policy benefit Disney? Sure. But it's also the only way to police abuse of the system. Without some financial penalty, folks will continue to book unneeded duplicate reservations just as they have in the past.
I can't see many folks being nostalgic for queuing up at a computer terminal to try and get dinner reservations day-of.