It all depends on the definition of "class." Originally Class was a straight-jacked, level 1 on, telling you everything you could ever have for gaining experience points. If you were one of the privileged classes that used the Spell Lists that ate up 40% of the PHB page-count you could actually enjoy flexibility and customization. If you weren't, well at least you could choose weapons, right?
As the game evolved and improved it added in more chances for customization outside of class and spell selection - sub-classes, non-weapon proficiency, multiclassing, then kits, feats, skills, and prestige classes. Finally we even started to see things like backgrounds, themes, and honest-to-goodness build options.
D&D has evolved to a point where the crunch can support archetypes without having to simply add another half-dozen straight-jackets to the rack with each splat-book. Having core Super-Classes with variant sub-classes / builds and combining them with Backgrounds and Themes allows players to build things that they used to have to wait for splat-books for (swashbucklers, knights, marshals, etc.) or perhaps never even get.
Old-school games can still be master archetype + improvisation.
Games using Build Options, Backgrounds, and Themes should allow us to create variants off of the Fighter, Cleric, Rogue, and Magic-User without having to have "new" classes spoon-fed to us with all the accompanying dysfunction of trying to carve a whole stand-alone class niche mechanically when we're really just looking for a few points of mechanic variation.
I want a D&DNext where my "Monk" is not a straight-jacket. I want to take a Fighter, have a "martial-artist" build that trades down armor for movement and enhanced unarmed attacks. Then I'm going to slap on whatever background I want, take a complementary theme (perhaps representing a martial-arts discipline), and beat people into submission with Combat Superiority mechanics for trips, throws, grapples and all the other martial-arts mayhem I like to associate with the monk.
I don't want a Monk were I have to use a list of Japanese peasant weapons, evolve immunity to disease, and automatically be a slave to "flurry of blows" mechanics because my attack-bonuses are lame otherwise.
Give me the ability to build a Fighter into a Monk like that 1E or 3E monks if I so choose, but don't give me a straight-jacket labeled "monk" and tell me to love it or leave it like AD&D -> 4E have done to varying extents.
- Marty Lund