Accidental release or not, if they were attempting gain-of-function, which is bio-engineering, and they succeeded, that deserves inquiry. Especially if U.S. leadership, WHO, or NGOs were involved.

To me, the "strength" of the covid-19 is evidence of successful lab experiments, not a fluke contagion. As the pandemic variants showed, natural evolution of viruses tend toward being less lethal. So why did Sars-Cov-2 start overpowered and get weaker?

As viruses can make the jump from one species to another, then it should not be hard to imagine how easy it would be to engineer that same outcome; that is all "gain of function" experiments do: try to emulate a pipeline for viral mutation.