Why Is Protecting COVID-19's Origin so Important?

Concerning the origin of COVID-19, last March The Lancet published a letter by prominent scientists calling rumors that it came from a lab a conspiracy theory.   

Dr. Meryl Nass, a physician with a three-decade background of knowledge in biological warfare:  "If the current coronavirus... is better adapted to binding to the human ACE-2 receptor than to all known animal ACE-2 receptors, then it either:

"1) mutated that way by jumping from wildlife to humans long ago, subsequently optimizing its ACE-2 receptor for humans over a prolonged period of time, or

"2) was genetically engineered in a lab to do so, or

"3) was passaged through cells with human ACE-2 receptors in order to accumulate the mutations that made it most virulent to humans."  

COVID-19 has not been seen before in humans, so we are left with hypotheses 2 and 3.