Perhaps because it’s too expensive to test every test for specifics?
This is silly.
True, the PCR test does not identify variant. Variant identification is done via genome sequencing. The identity of the person associated with the sample is not retained when the genome lab is provided that sample. And the genome lab is not provided all samples.
Why would it be? Their job is to measure how prevalent the variant is in the total population. Not what one person had.
Now if you’re in a region with 90+% delta, well, then again, you don’t need the lab to tell you. For you, personally, it won’t change anything for treatment (or death).