I've pulled a couple hundred feet of 25 and 9 strand serial cable out in LAN conversions over the years.
If you've pulled cable, you surely know that there is still plenty of it up there, down here, and around the corner. I doubt it is completely gone, given some of the things I've seen.
Sometimes I wonder if it is left behind "just in case" something fails so bad that VT100 terminals become worth their weight in gold...
;D