By my reading of the context, he's not talking about DPoS or the code base, but the social layer. What we have now is a bit different (e.g. free downvotes) from what Dan "invented" (to what extent others on the original Steem team contributed to the original conception, I don't know) and worked on, but mostly similar in terms of voting for rewards. Given his history of developing it and analyzing it, I do think it is fair to say he understands the failings of it pretty well, as he claimed. Nothing we've done since has been a real game changer.