The PR is in bad taste: positioning a paid offering as the logic next step for learning Rust does a tremendous disservice to new learners. It's clearly marketing for their company—what I would expect if CodeCrafters had underwritten producing the free tutorials, or at least put in the effort to gather a diverse mix of next steps, not what I would expect an OSS repo to provide to a company for free.

That being said, everyone claiming it was "shady" is off base. Sarup didn't make any effort to hide his affiliation (I personally would have assumed my affiliation is obvious if it's the first line on my GitHub page) and if that was the intent it would have been trivial to use a sock puppet account.