Pretty sure this is not true. A red blood cell (RBC) is approximately 8 microns across. The entire SARS2-CoV virus is 0.3 microns. Of that, the spike is likely 1/10 that size or less. That’s 0.03 microns. So an RBC is well over 200 times larger than the spike. Doubtful it could harm one.
I call BS. The spikes ain’t big enough.
What does a RBC have to do with it.? Clotting is a factor of your platelets. If the wall of a blood vessel is damaged platelets will rush to the site of injury and form a plug or clot to stop the bleeding.
https://www.verywellhealth.com/thrombocyte-what-is-a-thrombocyte-797228