I don't think everything has to be "modernized" and "updated." When I look at software from the 80s that is still with us, I think: "This is robust, keeps working, and has withstood the test of time" not "This must be changed." I still use C and the standard C library because I know how it worked in the past, I know it works today, and I know it will work for decades to come.
(minus the known foot-guns like strcpy() that we learned long ago were not great)
(minus the known foot-guns like strcpy() that we learned long ago were not great)