This was explained on MedCram and other medical sources two or three weeks ago. It attacks your hemoglobin cells and attaches to the hemoglobin receptors that normally transport oxygen.
I saw a rebuttal of the Heme attack and disruption by a Phd and MD all in one. I didn’t buy it because the explanation you refer to seems altogether logical.
Bingo! I read those reports a couple weeks ago. It's not the lungs, it's the hemoglobin's ability (or lack of) to grab oxygen. How can so many other scientists and medical "experts" be so wrong in the attached article on this thread? Sars-CoV-2 strips away iron ions in hemoglobin cells, so they can't absorb oxygen let alone transport it to organs throughout the body. The lungs are tossing oxygen, but the blood won't receive! Failed passes. So the liver starves, the kidneys starve, the brain starves, every part of the body is starving for oxygen. Meanwhile, the freed iron ions wreak havoc in the lungs and destroy cells there.