[dubyah]

The particular issue is, why specifically mention "sometimes higher" if there are no studies to back up that assertion or if you're going to rationalize your assertion on inferences about statistical noise? "Sometimes", "could", and "can" are doing the work of Atlas here. It's a genuinely pointless thing to say and somewhat bewildering to see someone continue to defend.

It's important to note the population of those 3 studies. For generally symptomatic individuals that sought testing, were hospital system patients, or were contact traced individuals, respectively, viral loads(Ct values) are similar between vaccinated and unvaccinated.

Even your first cited paper mentions deficiencies for asymptomatic individuals: >It is also difficult to determine the rate of asymptomatic or paucisymptomatic breakthrough infections and to ascertain whether viral loads in such cases are as high as those in symptomatic breakthrough infections. The “true” proportion of breakthrough infections with high viral loads would require comprehensive, frequent surveillance testing of vaccinated populations to identify these individuals.

The REACT-1 study data is from a large, random sampling of the population.