I don’t think so. High viral loads lead to more spread, right?

So if people have less comorbidities and that contributes to both less spread and less severe infections it should reduce contagion. Or I suppose contagion is still occurring but isn’t detected because the infections are subclinical and the host never even tests.

Only if they are randomly testing all citizens at all times.

People test themselves because they feel unwell.

If you catch covid but don't feel it, then you'll go back to normal without ever testing and thus ever knowing you had it.

If this happens for many people in a country (because of whatever reason) then you could easily have 50-100x the recorded numbers but nobody would ever feel it.