I think you are perhaps conflating returns on the fund as a whole vis-a-vis returns on an investment by investment basis. The goal of a VC, as I understand it, is to only invest in companies that can provide 10x returns, providing that one of those investments does return 10x, one returns 2x, three break-even, and five are outright failures. If a VC owns 10% of a company that exits for $3B, then the VC gets $300M, which returns 75% of the total fund. I very seriously doubt any VC firm would have stopped this transaction.