In the time of Exchange 2007 if you had a server with the active directory role on it, installing Exchange on top of it removed the ability to remove the active directory’s role later on.
In newer Exchange, like Exchange 2016, does this limitation is still there ?
Yes, the limitation is still there !
You can see the text there; Installing Exchange on a domain controller is not recommended
Demoting a domain controller to a member server isn’t supported.
I wanted to talk about it, as I still see some question about that, like seen there on ServerFault’s forum.