I would create many websites if I had a lot of interests that would be easy to write about as long as the niches had moderate to little competition.
Presently I've three that are easy to publish content to.
As far as making a living from them that remains to be seen.
They do produce enough to keep me pressing toward my goal of rolling

in passive income someday.
I rarely get discouraged because there is always an affiliate sale that fuels the passion to publish more content.
Let's put it this way, I'm making a whole lot more than when I first started and the possibilities are only limited by me of making more.