The reason for this I heard by Microsoft was to stop having to explain to non technical people that Azure AD doesn't have feature parity with a real Active Directory.
There is an experimental flag[0] in the .wslconfig which let's you set autoMemoryReclaim to gradual or dropcache. On my laptop I had good success with dropcache and on my countryside desktop with gradual.
As someone using both equally often, I am kind of certain Android passes through the raw sensor readings while iOS has some form of debounce delay and guesstimation implemented. Both are equally often off in their readings. But that's just based on usage experience, not a hard fact.
I don't recall the exact context anymore but during the Microsoft Build this year it was said by an employee at Github that the service came with the acquisition which is the reason it was and stays C#.