Dated!? Try timeless. The Grateful Dead span too many styles and so many years to be locked in a box. There is much to discover within the Dead. Many folks aren't willing to attempt such a grand leap. Too daunting. Zappa has a similar wide scope. Most music fans give up. They need bands that make 25 hit singles. It's easier to inderstand.
Blogger here is correct. GD are THE great American r'n'r band. Musically and socially. History will prove this as a fact. They left everyone else in the dust. Congrats for the insight.