https://source.colostate.edu/why-gain-of-function-research-matters/
In the current debate around SARS-CoV-2, the virus that causes
COVID-19, gain of function has a much narrower meaning related to a
virus becoming easier to move between humans, or becoming more lethal in
humans. It is important to remember, though, that the term “gain of
function” by itself covers much more than this type of research.
Gain-of-function research that focuses on potential pandemic
pathogens has been supported on the premise that it will help
researchers better understand the evolving pathogenic landscape, be
better prepared for a pandemic response and develop treatments and
countermeasures.
But critics argue that this research to anticipate potential pandemic
pathogens does not lead to substantial benefit and is not worth the
potential risks. And they say getting out ahead of such threats can be
achieved through other means – biological research and otherwise. For
instance, the current pandemic has provided numerous lessons on the
social and behavioral dynamics of disease prevention measures, which
could lead to robust new research programs on the cultural aspects of
pandemic preparedness. Understanding when the risks of gain-of-function
research outweigh the potential benefits and alternatives, therefore,
continues to be subject to debate.