I presume you're doing free dining which means you have to pay full rack rate for POR. To me there are potential savings and potential additional value. One needs to look at both and decide where
DVC does or does not fit for them. For many it doesn't but if you're going routinely, it likely is a reasonable choice. For POR you'd be best comporting to OKW or SSR in a studio to get as close to a direct comparison as possible. 75 points will get you a studio at those places and most others for most of the year for the 4 nights. Say $5000 buy in and $375 a year. Add $200 per adult (rounded) QS plan and $300 per adult for a 5 day pass. So for 2 adults you're looking at $1400 a year plus the buy in and time value of money. Of course your party makeup will change the numbers if different. While I think it's reasonable to assume a discount for value and moderate locations, I don't think one can count on FD continuing. Used most years, I think DVC will save you a little money and give you a lot more for your money. This assumes you could pay cash up front, aren't targeting the POR rooms that sleep 5 and will go routinely at least every other year (EOY).
What would actually happen is you'd have more costs up front and less later on. Personally I'd look at a return of the up front costs over 10 years. As I described it, you'd likely pay a little more over the first roughly 10 years but less after that and long term. However, the reality for most is they don't stay with a studio and thus pay more long term but hopefully get even more in return. But the savings is relatively low and there is risk and commitment so whether it's worth it to you depends on your situation and preferences.