"Ford, Ferrari, Porsche, Marantz are still in business. The founders are long gone." So is ARC.
You need to play it smart like Bill Johnson has. Selling the company 2-3 years before passing away although it should not considered as a "one man operation" before Bill sold ARC. ARC will be around for many years to come i am sure.
I anticipate 2 more will be folding shortly. Benz and VDH as both owners/designers are getting up in age. Too many one man operation business have no succession plan. No sons or daughters interested in continuing the legacy. The owner/designer dies, the company folds.
ARC is an exception and so will VPI as son Matt will take over from Harry eventually. I'm sure there will be others.......i hope.