This is why you ask a lawyer to write your license.
Re:Facebook Joins the Rust Foundation
by justapassenger on Thursday April 29, 2021 @05:12PM
(#26986778)
Lawyer won't be able to make those basic decisions for you. They'll be able to help write it in a way that has chance of being enforceable, but if you don't know where you want to draw the line, they also won't
Is only serving ads or also using ads not allowed?
Given that almost every single company in the world is using advertising then it becomes a hobbyist tool.
With serving - how about if I have a page/app that includes ads served by third party (like most of the world does). Does it make it also off limits?
Statements like that sound pretty cool, but ignore real world complexity.