I actually believe this to be the case. From what I have read researchers often do something called gain of function research. In this research they add genetic features to viruses that could make it more infective. This is done, at least in part, to help learn how to protect society from such a virus if it were to evolve naturally. I thought I heard somewhere that one of the functions coronavirus has that its closest known relatives do not have just happens to be something that virologists frequently add.
All this leads me to believe it was created in a lab. Likely for altruistic purposes but still. When this escaped whoever knew that it was from a lab should have disclosed it ASAP to help the world prepare.
I have no experience in virology so don't trust me.