Irrelevance. The moment you paywall a project, it’s a death sentence. Unless you have a unique and highly sought-after product (top 1%), someone else will just make a free alternative.
Well yes, but that accomplishes the goal of not working for free. Either you get money for your work, or your users move on, freeing you of the burden of supporting the software.
Exactly, that's an example of a top 1% project. It even has a detailed Wikipedia article in 35 languages. That model won't fly with small to medium-sized, regular projects.
If you have just thrown the code out there, in case someone can use it, then who cares? If it's not something you intend to spend more time on, what difference does it make?