I’m not so sure about that. FOSS is unlikely to gain a direct profit motive, and if it does, there will necessarily be versions with those features removed. How can you stop me from turning off ads or updates when I control the entire operating system? That’s kind of the whole point of free and open source software—the user is in control. Myself or someone with the appropriate skills can modify the code not to do those things. If that results in a better product, everyone will switch to it, killing those features permanently.
I have no problem with an open source AI if it proves useful, but it will be running on my machine under my terms. In fact, I already have an LLM running entirely locally.