Earlier quoted context omitted.
Some of these stories sound a bit far fetched, especially those that involve Unix systems. RCS was released in 1982 and CVS in 1990 so Unix systems have had version control available for over forty years.
There is a lag between availability and mindshare to apply a technology. I myself introduced SVN as versioning solution to a company in 2007, years after git was available I and I was aware of it git simply didn't have the mind share jet, thus I went with what I knew
In 2013, I was tasked with writing wrapper scripts around SVN to make it look like SCCS to avoid confusing the development people who only knew how to use SCCS whilst the company migrated to SVN. Fun but traumatising.