Isn't it equally likely the opposite - your comment presumes that Vanguard is using money from passive to prop up active, whereas it could also be that money from active is already being used to lower fees on passive?
And what happens if active fails? Then passive would take the hit even though people go with Vanguard specifically for the low-risk passive.
And what happens if active fails? Then passive would take the hit even though people go with Vanguard specifically for the low-risk passive.