CVS is in use many places, especially in decades old source trees where migration would result in the loss of to much metadata or to much build automation is dependent on CVS. I personally know of several instances of this.
Windows 3.1? I run into it occasionally in places like manufacturing where upgrade cycles are decades long (was recently at a client who's most critical machine was built in 1905). FWIW, DOS can still be found everywhere.
Magnetic tape? Really? LTO-6 is up to 2.5TB uncompressed and LTO-7 is imminent.
Punch cards? See: Scantron.
Just because there's a cool new replacement for something, doesn't mean you should jump on it, or that the old tech is now worthless.
Windows 3.1? I run into it occasionally in places like manufacturing where upgrade cycles are decades long (was recently at a client who's most critical machine was built in 1905). FWIW, DOS can still be found everywhere.
Magnetic tape? Really? LTO-6 is up to 2.5TB uncompressed and LTO-7 is imminent.
Punch cards? See: Scantron.
Just because there's a cool new replacement for something, doesn't mean you should jump on it, or that the old tech is now worthless.