I think this is very interesting. I've never stayed at the Poly, but I've visited several times & I've always wanted to stay there. Although I loved all the plants, the landscaping, and the waterfall, IMHO the resort does look "dated" and I'm personally excited to see how it will look when it's finished. If the rumors are true and it ends up looking something like Aulani, I think it will be terrific.
I haven't looked at occupancy rates, I always assumed that the Poly was high, based on all the positive Poly feedback on the internet. However, if the Poly has particularly low occupancy, it may be struggling with a problem that is common to hotels - and more so to restaurants and retail stores.
Basically, they have a core group of "fans" who have been there many times, love it the way it is, and don't want anything to change. However, people who aren't already attached to it don't feel the same way, and are more likely to see all the flaws since they don't have that "history". Over time, the hotel/restaurant becomes less and less popular, as that core group dwindles over time, and fewer new people are interested.
If occupancy is down, you lose some rooms to the DVC, and occupancy shoots up. The DVC pool is limited, so you're pretty much going to have to own there to stay there, leading to a quick sellout - both from new people and add-ons. The resort is full, DVC owners are happy, and Disney makes a boatload of cash quickly. So, from Disney's perspective, I can see that it's a win-win.
The only people who lose are the people who like things "the way they used to be", but since change is constant, those people lose everything, everywhere (not just at WDW), all the time anyway.
As for the DVC cost - I don't follow DVC that closely, but from my recollection, DVC has never charged drastically different prices for resorts that are on sale at the same time. For example, many people thought DVC was going to charge $175 per point for VGF, and they surprised a lot of people by only charging $145 per point - similar to existing resorts. They made up for it by charging more per point. I wouldn't be surprised to see them go this route for the Poly as well. I'm almost wondering whether the Poly could finally be the first "investment property" in the DVC - if owners could charge enough of a premium when renting points to make it a worthwhile investment.