Is the death of American design greatly exaggerated?  

Yeah, whatever. But to address SDR's main question...
No, I don't think the Aeron will be admired in the future as we currently admire the iconic mid-century chairs that were designed using then-new technology.
The Aeron's big problem is that it ISN'T new. That is... Its various pieces are the product of recent research, but the chair as a whole is just the ultimate (so far) realization of an old-fashioned idea: That the "best" task chair is the one with the most knobs and levers.
The Aeron's sorta like an audiophile turntable: expensive, and with a whole lot of adjustments to tweak and fiddle with. When I want to listen to music, I have no interest in getting out a protractor and setting a turntable's VTA and azimuth, measuring its motor speed, selecting weights for its tonearm, adjusting its anti-skate, etc.; I'd rather just throw a CD in a drawer and press "play".
It's the same with a chair. Why do I need to twist all those knobs and pull those levers just to get comfortable in the thing? Why can't it just adjust to me automatically?
If the Aeron's admired at all in the future, I think it'll be by engineers and engineering-minded hobbyists... The way that those people currently admire complicated old mechanical watch movements or automotive carburetors FOR their complexity.
In my opinion, the next task chair that'll be admired for its design will be the one that dispenses with all the adjustments because it just works, for everyone, without them -- the way digital watches just keep perfect time without regular adjustment by a watchmaker, or the way cars with electronic fuel injection just work under all conditions without any of the ridiculous tweaking that carbureted cars required.
But that's just my opinion.

Until designers are willing to think about the cage they are kept inside...
and try to redesign it, rather than just say "yea, whatever" about their cage, they will continue to just be used and abused to develop sizzle for increasingly oligopolized markets.

My intention was to elaborate...
...on what we have learned on function, as the third engine of innovation, but I would like to comment on SDR's contribution and question first. Herman Miller's Aeron chair certainly is a classic and we will not have to wait for decades to get this confirmed. But, as pointed out by fastfwd it is a classic of the end of a period. I agree that there are a number of interesting technologies incorporated in this HM design, but it certainly does not take into account all we know about the seating position and how it affects in the short and long term our physical condition. Furthermore it has become the symbol for working conditions that none of us really wants: It expresses and perpetuates the difference between blue and white collar workers (how many Aeron chairs have we seen behind machines where workers are indeed seated almost 8 hrs per shift?) and it is designed to be comfortable beyond reasonable alternating periods of work and rest periods or periods of immobility and mobility. I think it will become the symbol of a time when the search of efficiency was still a higher priority than looking at working conditions in a humane way. Compared to the virtual product of Fiberforge it has of course the advantage of being a finished product.
Fiberforge on the other hand has no product. The car they worked on is like so many other things a promotional gimmick. Within both manmade legislation and the laws of physics there is no room for carbon fibre car bodies. There is hardly room for anything but steel. When a car crashes, the energy of the forward moving mass has to be transformed into another form of energy. Right now we do this by using a material that generated a lot of heat when bended. Considering that heat loss of an equal amount of calories is faster at high temperatures than at lower temperatures, we build car bodies in such a way that these bending lines generate as high temperatures as possible. Steel does just that and steel does it better than any other affordable material. Fiberforge, as their website explains well is a technology company. It promotes the use of a particular process in which carbon fibres are use in combination with a thermoplastic and formed under pressure and cooling. It is a very suitable process to make lighter car components, but one particular technology is a bad start for a product of the complexity of a car. Those who witnessed the dominance of steel for everything and anything in a car know what I am talking about. Complex products require complex solutions and a large diversity of manufacturing technologies. To promote one technology by association with a non existing car is what BASF or Bayer did with the Luigi Colani prototypes, but it should not be considered a contribution to a real solution.
And...Welcome back Chewbacca rug