You're probably not gonna believe it, but it's because they don't know much, especially the context in which they're making decisions.
How could they really? The reality of any company is not its ideas, but its implementation details. For tech companies that's really difficult.
You know how everyone with a room temperature IQ keeps insisting that AI is gonna take away programming jobs? Imagine that it already happened except that instead of losing your job you have been left to manage the robots... that's the position they're in, but the robots are instead extremely stubborn 20-something contrarians who want to rewrite everything in Rust.