The clots.
They’re why the ventilators didn’t work.
Interesting article.
Agree. Do "more than 30 percent" of flu sufferers develop blood clots? I don't think so. Blood clots in blood vessels leads to damaged vessels which remain with us for life. The body has ways of growing new vessels, or enlarging surrounding vessels to take over for damaged ones in some cases, but the damage is done, and this probably explains the permanent lung scaring, heart damage, and etc., seen in covid patients.
Ventilators work as well as they do for any other etiology of ARDS. The mortality rate on ventilators is about 35% same as with other causes of ARDS