This becomes a true statement if someone who purchases RIV directly immediately sells it at an actual loss, which would have been a bad investment. Otherwise, it's a "paper loss" and one I don't spend much time fretting over.
Every
DVC timeshare, if held long enough, will be worth zero dollars. For many people, the value of the purchase is derived from its use, rather than its potential resale value in a fluctuating market. A direct buyer of points receives the same value (in points) from their purchase annually, provided they hold their contract until expiration.
We have bought both direct and resale points over the last 25 years of membership. We purchased RIV directly because we loved the resort and didn't want restricted points.