Smarter than us.
Seems like this coronavirus mostly causes the common cold.
The anti body tests are no more faulty than the way we keep the statistics for covid 19. Probably less so, as scientists in LA, NY, Germany, Sweden and Italy all use antibody tests to predict the true number of cases.
I agree with your sentiment of wanting to get a more accurate anti-body tests.
Before that I want more accurate data on how many people actually have covid-19 and who was actually killed by it.
Should be no assumptions. They should know from a test not just symptoms. If you die from it they need to cite what underlying health conditions they had if any. Toss out the superficial data so we can have a better picture of this.