Maybe I'm misunderstanding this but a 0.5% false positive rate and a 51% positive rate means that you still get a 50% TRUE positive rate instead of the current

Maybe I'm misunderstanding this but a 0.5% false positive rate and a 51% positive rate means that you still get a 50% TRUE positive rate instead of the current rate, which is 0%. And then after you can follow up with a test that is more accurate. Everything has an error rate, even pregnancy tests do, and nobody argues that we should not use pregnancy tests.