The 911 will always be a collectors item because it has a unique signature; Its shape. No question about what brand or model when you see one as there is no other vehicle that looks like it. That exclusive look and the racing heritage it racked up (and continues to rack up) makes it desirable for car fanciers.
The bicycle should be judged on the same standards. When you see it, you know what it is (Hetchins for example), it has a lineage that is noteworthy (Colnago or Coppi), and has technology that is unique and changed the way the machine functioned (Campi toothed dropouts and lever shifts). These are a few examples and not the only ones.

As for Riv, Grant Petersen is a marketing genius. I respect him for it and for bringing common sense back into cycling. At the time he started on his own, the compact frame was making an entry into the market, racing was all the rage, and the common man non enthusiast was wondering why road bikes were so uncomfortable.
Grant declared the old designs were not outdated and made more sense for most everyone. Singlehandedly he steered the bicycle manufacturers toward taller front ends, longer stays and more comfortable riding positions. He did this through persuading the riding public that common sense was indeed fashionable. It started at the top end of the market and has made its way to the bottom. Trickle down if you will. Thank goodness others saw what he saw and financed the venture. The cycling industry is better off because of it.
Rivs are really well made and good looking machines. No doubt the originals will be collectable at some point in time. They represent a fella that took a gigantic risk and defied the big guys, went with old school designs, materials, and construction methods and influenced an entire industry to redesign. He influenced a huge rebirth of the independent fabricator of bicycles. The small, one at a time maker of artful bikes.
Can't fault him for any of it.