Arnold,
I left XVT around 1992 or so and shortly after that it was absorbed into a California company owned by XVT's VC investor. Then the XVT assets were sold to someone and it was operated for some years as an independent company, but I don't know what happened after that. I haven't had any contact at all with XVT for over 30 years.
Poking around, I see this website:
where XVT seems still to exist. But that's just from Googling; I don't have any other knowledge.
Indeed XVT supported character displays in addition to GUIs.
Marc