I lived through the Eighties (barely) without once hearing Van Halen referred to as "Halen." Is that a Millennial (or whatever the hell you fledglings call yourselves) thing ?
I proudly grew up hesher in SE Portland in the day, with a Showcase Music 1/2shirt circa 1985 to show for it, and quite often heard Van Halen referred to as "Halen", similar to Black Sabbath being referred to as simply "Sabbath".
OK, OK, maybe I just blocked it from my memory, along with the aftermath of that 1983 New Year's Party OH CHRIST IT'S ALL STARTING TO COME BACK TO ME NOW!
doesn't make it right, though.