With regard to datacenter operators, I would argue that a simpler answer to that observation is that they are investing heavily in the are in which they can actually effect change. That is, they can swap in-and-out their hardware, but language of choice is largely up to their customers - the dev. They can advocate and champion a particular language, but really enforcing it in any meaningful way is narrow casting their own user base.

They could offer their own compilers or runtimes. Some big companies do. But most dollars and time is spent on hardware R&D and upgrades.

Facebook and Google both have in house chip designers these days, specifically for their data centers.