As other said - the resale buyer will not be able to trade into any other resorts -
which will undoubtedly hurt resale prices, though it's hard to know how much. It IS a Disney property, so I won't think it will go too low. But I wouldn't be surprised if the price is lower than typical for the newer resorts.
Honestly, if I was going to consider a buy - buying a guaranteed week in a studio (or tower studio) during a popular time of year would be the best bet for retaining value - while not everyone would be looking for it, I would still think it would gain more interest on resale, even without the ability to trade out. And while I have to admit the resale issue is a fairly big turnoff - I have always said that you should NEVER consider resale value as a primary concern for a
DVC purchase. First of all, as they near the end of their lease, the value will eventually drive to zero. But even bigger, if there's a MAJOR economic downturn (and there will be a some point) resale prices are likely to drop severely. Disney can always shelve plans for building DVCs, but the resale market could take enough of a hit that Disney doesn't ROFR much and prices could drop IMO by 50%.
The final point is if you want to buy direct, it's not like the resale rule changes are going to improve with the next resort. You are essentially "stuck" with this rule wherever you buy going forward. (The "old" resorts will still always be able to access the old L14 resorts.)