Is there a strong reason why Microsoft chose not to support AppDomains in .NET Core?

AppDomains are particularly useful when building long running server apps, where we may want to update the assemblies loaded by the server is a graceful manner, without shutting down the server.

Without AppDomains, how are we going to replace our assemblies in a long running server process?

AppDomains also provide us a way to isolate different parts of server code. Like, a custom websocket server can have socket code in primary appdomain, while our services run in secondary appdomain.

Without AppDomains, the above scenario is not possible.

I can see an argument that may talk about using VMs concept of Cloud for handling assembly changes and not having to incur the overhead of AppDomains. But is this what Microsoft thinks or says? or they have a specific reason and alternatives for the above scenarios?