I work in a field that is considered by many high tech. I have personally seen a system in use today that duel boots windows 2000 and windows 98.
The product it's used by is old generations and the system does not have any network access but still must be supported by government regulation for several more years....
I think it was 2017 we got rid of our last system running freedos in a console since the original program required do to operate...