As a brand new owner of resale it seems to me that hurting owners of resales only hurts
DVC in the long run. If Disney isn't willing to buy ownership rights back and hurts the resale market through making ownership to burdensome or changes the privileges of resale owners to much, why would anyone buy new knowing that it would be almost impossible to ever sell if they got tired of it.
To me if they want to control the resale market they need to start exercising their right of first refusal and buy more properties back. This would likely inflate the market overall at least for a while and make buying direct more attractive.
Disney can obviously do a lot of things that could make buying resale less palatable but I think they would only hurt themselves in the long run since I would expect sales to come to a screeching halt if it is to drastic. I would have never bought if I thought I was going to throw away $20K. I didn't expect a return on my investment but I sure don't expect it to be gone for ever unless I keep the property through the end of my contract which it probably not likely given my age.