I mean, I guess. On the other hand, if you have a niche side project (I have several in a rather niche language), then you become known in the community.
Most people's 'side projects' don't shine on their resume because the side project is just a replica of one hundred other projects that do the same thing. In order to be known for a side project, you have to make sure the audience is small enough for it to make a difference, but large enough that there is commercial interest.