Totally wrong. Take a sample out in 15 cycles. Take a sample in 30. Run a gel. Compare. Done. Most of the issues you think exist are because an RT pcr machine cannot distinguish between primer-dimer and pcr product. A gel can distinguish.
This argument is pointless as the assay relies on a dual-labelled probe. Look up how that works [1].
Anyway, an end-point PCR is not quantitative. You could do semi-quantitative on a gel, but it's a rubbish technique that was rightfully forgotten years ago, as it requires a lot of optimisation and has very little reproducibility.
You seem to miss the point entirely. The point is that the assay doesn't NEED or REQUIRE dual labelled probes at all. The only need for quantification at all is to avoid mistaking signal for spurious noise (e.g., primer dimer). The gel provides both semi-quantification and provides amplicon size, which massively increases specificity of an end-point version of the assay. It is perfectly adequate.
The larger point is that there are many ways the test could have been designed around any possible combination of supply roadblocks (no DNA extraction reagent, choose phenol/chloroform; no cotton swabs, use paper; I could go on and on), so there are no excuses as to the massive and unwarranted and fatal delay in rolling out comprehensive testing in the U.S. Sure some work arounds are less desirable, but the alternative we have chosen is to fail a number (~>5,000) of people who didn't have to die by letting this thing spread without adequate testing.