Why is there no way to cross save between game pass and Steam?

Other steam games where you can login to your xbox live account like Sea of Thieves just synchronize the progress between the platforms(just like you would expect). Why else have the option to login with a global account?
What is the reason for AoE 4 not to have cross saves and is there any possibility this could be added in the future?

I had 200+ hours in the game pass version, bought the steam one and cant refund it anymore.