And that's the key to this whole thing. They do have a history of it - with high pressing and a ridiculous work rate comes a down side. And that was exactly Liverpool's problem for the first few years under Klopp.Not really lazy when Bielsa sides have a history for it.
While it was unlikely Leeds wouldn't have still won the league and been promoted without COVID it's not unreasonable to say it helped them based on previous evidence relating to Biesla's sides. If that's all she's saying then I don't really see the big deal.