timewizard parent
Presumably there would be an open call where people would nominate themselves for consideration. These are problems that have come up and been solved in human organizations for hundreds of years before the kernel even existed.
There is no call. Anyone can volunteer at any time.
Software take up no space and there is no scarcity. Theoretically there could be any number of maintainers and what gets uptake is the de facto upstream. That's what people refer to when they talk about free software development in terms of meritocracy.
How would they know to volunteer? Are you saying I can perform a hostile volunteering to take over for a maintainer who does not want to give up the project? I don't think you understood what was meant.
Anyone remotely suitable would be active on the lkml.