YouTube have such a stranglehold on the >1m market, that’s why they can afford to stagnate in that area and look into other markets. They don’t have to fear a competitor threatening their core market any time soon.
The problem with randomising the test order is that it compromises the reproducibility of results. If there are ordering issues, then your tests will sometimes fail and sometimes pass, but will developers look at that and think “ah there must be an ordering issue” or will they think “damn these flaky tests, guess I’d better rerun the pipeline”?
His interview certainly lent some additional weight to the theories that he’s been trying to run the company into the ground the whole time.