No, it can't. More contributions require more maintainer effort, not less, if you want the project to follow a design and pursue a goal, rather than be a kitchen sink.
Yeah… no. I’m working on a pretty important project at my job that needs to be done well and as fast as possible without sacrificing quality. I’m writing code solo because I know exactly what I need to write and having to keep a second person in line would use so much time and energy, I wouldn’t get work done.
Don’t worry about the bus factor, other people know what I’m doing and I have a backup who can take over. Might delay the project a month or two, but the company can manage without me.