Leverage funds are all in basis trades. Long cash treasuries short futures. Asset mangers are just long futures in their books. The leverage funds repo their cash Treasury positions daily overnight. Say the implied repo rate is 5.85% to be long cash short futures until the delivery date. The leverage funds are funding this position overnight at 5.40 so picking up 45bps risk free till delivery on BILLIONS. These trades have downside for sure but overtime the fed has always come to the rescue and bailed out the street with funding liquidity.