Devils advocate here: it’s their webservice right? They determine who can access it.
If there were legislation that would force them to make it interoperable that would be one thing. But you can’t just demand access to their infrastructure.
After Max become champion for the first time, he was asked how important GP was to him.
He answered in the typical immediate and direct way something in the sense of: ‘very, I will only work with him. We are fully honest with each other: I will tell him when he fucks up, he will tell me when I fuck up. I won’t race without him as my race engineer’
Those weren’t his exact words but the sentiment is clear.
Well done Baku