None of you are old enough to remember the Sony hi-fi cassette, as sound is to video, so the hi fi cassette was to the Betamax - and
I was demonstrating the Sony surround sound format on reel - to - reel tapes by '68.

Two additional arguments to the thread
:
Philips (who have had their own failures(at least three other video formats)!) invented the compact cassette but Sony turned it into an acceptable format for widespread use.
Sony sit on both sides of the ripping/downloading argument, being both a record company and a hi-fi manufacturer: They must have some in-house politics!

What happened to the Telefunken cassette?: 2 ips and twice the width of tape, oh, well, up in heaven with the 8 track and I bet none of you remember its precursor, the King 4 - track!