Still waiting for one of those vaccines and boosters to kick in, apparently.

Yawwwwwwwn. LIEden has antibodies from a Covid vaccine and antibodies from having recovered from Covid (more than once, IIRC). Antibodies, regardless of source are not magic silver bullets that prevent an infection process from starting, especially respiratory viruses, which start doing their thing in mucus membranes rather than directly in the blood or lymph where antibodies are present.
LIEden's antibodies from recovery didn't work any better or worse than those from the Covid vaccine he received.