Honestly, I am surprised they are being critical of the way it was done. As I wrote earlier, I presumed a deal had been cut between these worthies and Joe Biden that they'd agree with his statement that nobody said stay in Kabul and they'd keep their jobs.
It appears they are arguing they recommended keeping a modest (2,500) force in-country to provide backbone (my term, not theirs) for the Afghan government and army. A very real factor was that our leaving probably meant the Afghan forces pay was terminated and effective air support disappeared when our techs who maintained 'their' aircraft went home.
As I noted earlier, theirs was a "sepoy" army, hired troops fighting for a paycheck that we supplied in a country with few good jobs. As an analogy, try to imagine what would happen to Britain's famous Gurkha troops if the London's paychecks ended, they'd go home to Nepal and be farmers maybe? That's what the Afghani troops did.
I haven't heard if the generals also testified the pull-out was badly timed and managed. Perhaps they believe, as I read yesterday, that if Biden insisted the pull-out be immediate, the way they did it was optimal as far as safety of troops then in-country was concerned. Obviously, the safety of U.S. and allied civilians in-country was not much considered.