It could set up a path.  One day, some miners are struggling so they decide to collude and mess around with a drivechain. Drivechain go south. A year or so later, the same miners are struggling, now they’ve already grooved the road to collusion.   People often overestimate the speed at which miner collusion would destroy the value. It wouldn’t be overnight. Plenty of time to take their profits and go do something else.