Said it before, will say it again:
The effect of the resale restrictions is greatly exaggerated.
1 -- Can only stay in 1 resort. How many DVC owners primarily stay in their home resort anyway? Do lots of GFV owners try to use their points at SSR? Lots of owners mostly already stay primarily at their home resort. I was just checking the inventory for 7 months from now -- There were only a handful of options for studios. No studios at BRV, BLT, RIV, GFV, BWV, BCV, or CCV. If you travel around holiday periods especially, trade options are very limited at 7 months. So owning at "just one resort" is not always much different than owning unrestricted points.
2-- Very soon, Riviera will probably be the only Epcot area resort with any long term value. BCV and BWV are both entering their final stretch. In 2030, there won't exactly be a big re-sale market for a contract with only 10 years left, while Riviera still has 40 years left. And with access to both DHS and Epcot, there will always be a demand for the Epcot area resorts. If you're buying now, you are planning on holding until at least 2030. So realistically, which of the 3 will have the best resale value: "Unrestricted" BWV and BCV with only 10 years left, or RIV with 40 years left. And if new DVC is added to the Epcot area, it will almost certainly have the same restrictions.
3--Any diminished resale value is already baked into the direct price. Yes, RIV resale may be less than GFV resale, but RIV direct is a lot less than GFV direct. For the reasons 1 and 2, RIV resale won't be worthless. For the right price, lots of people would accept the resale restrictions. So if the price is $30 less than a GFV resale, ok.... but it was a cheaper direct purchase too.
4-- Future resorts will have similar restrictions. And the old resorts will have the restriction of not being able to use numerous newer resorts. So in 15-20 years, the reality will likely be that the only way to get unrestricted is by buying direct. And all re-sale will have to deal with off-putting restrictions. A 15-20 year re-sale contract at SSR or AKV would have their value diminished if they couldn't be used at any of the Epcot resorts, for example.
To me, I can understand the resale restrictions pushing someone to buy direct as opposed to resale. But they wouldn't stop me from buying direct in 2021, because it might somehow affect the resale value in 2031-2041.