Earlier quoted context omitted.
I was under the impression that Windows Terminal is a recent greenfield project.
Yea. Microsoft has two terminals. Command Prompt (cmd.exe) which is the default that comes with Windows, has been around forever and basically never seen a significant update. And the new Windows Terminal which is the recent greenfield project that only works on recent versions on Windows 10 and doesn't ship with Windows by default (yet). Unfortunately people often get the two confused when talking about "the windows…
Conhost is the window that's had updates all throughout Windows 10. It's responsible for both the console subsystem, and the console UI. The UI though is the part that's largely being replaced by the Terminal. Conhost will never go away, but the Terminal is where all the action is these days.
(It's also shipping with Windows 11 by default)