For an aluminum bike, you are darn skippy Klein is a standard, model and guide.
I think if I was going to look for a sub-group of bicycle standard.... as in "Classic Aluminum" I wouldn't rule Klein completely out. However.... I don't see aluminum being discontinued as a bicycle material anytime soon. I'd need a crystal ball to guess at what will be considered to have been the standard for aluminum. Honestly.... I think much better examples of a standard of/for aluminum bicycles could be purchased TODAY.
Can an aluminum bike be a standard, model or guide for all bikes? Absolutely. Unless of course one has the silly steel is real bias. Then no.
Yes aluminum can reach the same level of standard... as steel bicycles have. But only (like steel bikes) after they are no longer standard production models. Currently.... aluminum is pretty much ubiquitous. It would be difficult to believe that these aluminum bicycles have reached their apex of quality.... OR that it was reached in 2004... and NOT 2014.
Steel bicycles however are different. Because they are no longer in real mass production. The old steel bikes do ride and/or feel different than modern bicycles. The quality ones made in previous decades are the "standard" or "classic" bicycles that are appreciated and collected. Enough people appreciate the old "real steel" to make them collectable.