There is a hypothesis that this is driven by the fact that VC firms are playing with other people's money, which must be "invested" in order to collect fees, an

There is a hypothesis that this is driven by the fact that VC firms are playing with other people's money, which must be "invested" in order to collect fees, and they often sell those assets to other VC-backed firms which are also using other people's money. In an illiquid environment with tons of collusion and principal / agent problems incentivising towards higher prices (and thus greater AUM), you'll tend to see prices diverge from those in a market open to anyone who thinks they can play the game better.