They can keep the cloud portal I’ll just have the container thanks 
Given the trajectory they are looking to ditch Windows and MS SQL so it would make no sense for it not to be. I could see some arguments that it keeps on prem Windows folks happy but, at the end of the day, docker and it’s ilk are incredibly easy to maintain. I could argue that compiling the Windows version is a single click in VS and you have a self hosted exe to run for the windows holdouts. Either way at this rate I’m struggling to see windows server be relevant in the next 10 years.