"The link-level ("link") address is specified as a series of
colon-separated hex digits. This can be used to, for example,
set a new MAC address on an Ethernet interface, though the mecha-
nism used is not Ethernet specific. Use the ("random") keyword
to set a randomly generated MAC address. A randomly-generated
MAC address might be the same as one already in use in the net-
work. Such duplications are extremely unlikely. If the inter-
face is already up when this option is used, it will be briefly
brought down and then brought back up again in order to ensure
that the receive filter in the underlying Ethernet hardware is
properly reprogrammed."
I do not think that _this_ was or will be ever an issue to myself or any system that i have to deal with and i do not see any use for it but i guess somebody else did. Anyway I believe this page is a very nice read on the background and a little history https://www.in-ulm.de/~mascheck/various/shebang/
"Looking back, we will see Covid-19, just like September 11, 2001, as a time when governments gained new, intrusive means of controlling their citizens."