Legends & Lore article on a Friday night? Just to clarify—because he did, at least on EnWorld—this article was apparently posted on accident, and (perhaps more importantly) he is referring to throttling the rollout of new crunch options/splatbooks, not rules modules, in favor of focusing on flavor material.
Reducing crunch could be good: I remember how pretty much every monthly release for 3rd Edition initially included feats, prestige classes, items magic and mundane, virtually none of which, for a variety of reasons, we ever used. The Complete series started adding classes to the crunch bag which, again, we almost entirely ignored.
Do not get me wrong: I like a lot of character options, it is just back then a lot of them did not do what they were supposed to and/or quickly became non-viable (fighters), rendered other class obsolete (many prestige classes, especially for fighters, sorcerers, and wizards), did not play well together (fighters and wizards), or did minor, fiddly things that were easy to forget, highly circumstantial, or both (many, many feats and magic items).
4th Edition, to me, at least got races and classes right (well, mostly right for classes: they had a lot goingon). I think that in my group we used virtually everything with the exception of some of the Essentials sub-classes, and even that is basically due to a lack of time. I even liked a lot of the racial and class feats, especially when a racial feat let you do something thematic within a class, though to be fair it had its share of fiddly feats, and until Mordenkainen's Magical Emporium I did not care for a lot of the magic items.
So while I was initially wary as to Mearl's statement of "sticking to things that make sense and resonate", I think this is what he is aiming for. Fewer, but more interesting, flexible, and meaningful options that work. Feats seem to be going in that direction, at any rate, by giving you several benefits, allow you to craft items, or cast spells, instead of just giving you a +1 to a stat, or +3 in very specific situations (though a few, like Sniper, seem to miss the mark).
The most important part, for me, is to be able to make a thematic character. I disliked the invoker not because I felt that the class was underpowered, but because when I wanted to make a tiefling that worshipped Asmodeus I was unable to choose enough interesting fire-themed prayers. If I wanted to go Raven Queen there was even less to go with, so when I finally got a chance to play one I was lucky in that my DM let me homebrew basically everything.
I hope that what Mearls is not saying is that we will not get things that we have not seen before, or depart from "tradition". The battlemind and shaman are two of my favorite classes, both giving you access to things that you really did not see before, at least not so early on in your career (though the former suffers somewhat from the lack of theme I mentioned above). The seeker and runepriest, on the other hand, are examples of classes that could have been folded into other classes (or become prestige classes), but could have benefited from better support and story content.
On the topic of story, I have fond memories of 2nd Edition campaign settings. Well, Planescape and Dark Sun, at any rate, probably because they were different than the typical fantasy fare. 3rd Edition also brought Eberron, which was also a nice departure from the more vanilla settings, so despite their often poor track record with adventures—as they have their share of gems—it is possible for them to churn out something decent story-wise.