rigable version of PoS which they termed DPoS
I guess I'll post my quote again below since you don't understand how standard PoS works. It's the same thing as DPoS, just less efficient, lower performance, more Rube Goldberg approach in implementation. PoW, PoS, and DPoS all use delegation and the act of voting for a delegate. Anyone who claims otherwise is flat out lying. If you dont believe me or dont get it, I dont have time to try to convince you, sorry:
For standard proof of stake, the end game stake scenario results in people having to pool or lease their stake, otherwise there's no point to stake at all. They're delegating their vote power to determine the longest chain to the pool owner. The act of doing so results in two things. First, you've recreated the centralization of PoW pool mining, where most of the blocks are being validated by a handful of people and one out of million being done by some random guy. Secondly, you've also recreated DPoS, just a less efficient, less decentralized way of doing so. Most blocks being signed by a few pools vs larger number of block validators in DPoS.