Surface grinders generally don’t use CNC, they are a simple machine.
This is a fun playlist of a conversion of a manual machine to CNC:
https://www.youtube.com/playlist?list=PLDlWKv7KIIr9rlCwZ9K43...
In the 1950's, yes. But these days they definitely are CNC based.
https://phillipscorp.com/india/phillipsgrinding/phillips-sur...
All you need is a serial port and some G-codes.