I can't see where the Fed Government should fund any and all willy nilly desires of each and every state. That's not feasible.
This is a trivialization of the Federal Gov't responsibilities.
States can't subsidize lab tests or provide incentives for labs to do more tests, states can't force manufactures to make more nasal swabs or reagents, states can't reduce regulations so testing is faster and easier...only the Federal Gov't can.
we don't have a clue to the value of Covid antibodies except to fill out the scorecard.
Any information about infection rates, locations of hot spots, demographics is valuable. The purpose of antibody tests is to find out how many people are immune and how large the proportion of asymptomatic cases are so states can monitor the scope and spread of the disease. This may help determine who can or can't go back to work or what areas or businesses can remain open or shut down.