I definitely like my coolant level warning light and would fix it if it
broke. It's 1 more piece of info.  something is leaking slowly, it will come
on.  sudden loss of coolant it will come on at least a little before the
gauge goes up.  More of an attention grabber than the gauge too.  Warped the
head in my first VW, 76 Scirocco, when I was a teen.  Driving up I-95 with
what turned out to be a faulty radiator cap.  Hmmm, what's that hot smell?
Check the gauge and it's at the top.  Maybe a  blinking light would have
caught my eye sooner.
Edward