I've always been suspicious about the strategy of drafting the best player available. I know many GM's and coaches "say" that's how they draft, but this is an example where it didn't work.
When trading partners realize you "need" to trade a position player because you're too deep at that position, the value of the player reduces, as we're seeing in this situation.
It's obvious that GM's around the league know the 76er need to trade one of the many young center they've collected, and are taking advantage of the situation.
Kind of similar to collecting too many future draft picks.