Nonbody removed any contributors. They just took away maintainer status from some people (rights to commit direcly to the kernel repo).
They are still allowed to contribute via the normal process.
They only removed him from the maintainer list, he can still continue to contribute normally (and he even says he will probably continue to contribute in the future commercially).
Russia doesn't frear NATO - see their reaction on Finland joining it. Also the pipelines were not the reason for invasion. They were the opposite - a deterrence. As soon as Russia built pipelines that were circumventing Ukraine, they decided to invade, thinking that the gas transmition would't be in danger now.
