Well, first of all, Mike certainly was familiar with things like narrativist design concepts, sure. But he wasn't IN CHARGE of 4e's design, AFAIK. Honestly its impossible to say who had what influence and what these different people advocated for. So, it is quite possible that the game went in a direction he NEVER liked and he may well have fought tooth and nail to change that, or he was just a good soldier and did his best to get his boss what he wanted, like most of us do every day. We know he wrote KotS, which IMHO does not speak well of his feel for what would work well in 4e...
And I don't think Mike should be singled out here. I never got the impression that WotC fully understood exactly what they created and how it should best be used.
Adventure design is one the ways this shows. Although later adventures were slightly better than KotS, none of WotC ones really took a Zeitgeist like design of one big map story important combat in between lots of other stuff (exploration, free roleplay, investigation, etc.) which was probably 4e's sweet spot. Or spread out the right amount of XP into multiple rooms that were expected to converge so it turned into one big regular encounter.
Rituals were also almost completely ignored in adventures. (and in the system in general). Imagine if
1) rituals were split into Arcane, Divine, Primal and you only got access to one list with your class (or the feat)
2) traditional full spellcasters like Wizard, Cleric, etc. got a few free Ritual casts a day and that was put into the class description in a Spells Per Day type chart. Say eventually One per day at Level -1, 2 per day at Level -2, and 3 per day at Level -3 or whatever. And got 1 free ritual added to their ritual book per level.
3) adventures assumed you might have access to some of these and enemies use them too
Rituals were such an amazing answer to "how can we have this kind of powerful utility magic that D&D is known for and not have it be tied to certain classes or too often circumvent combat encounters?". Then they completely ignored it, taking away a big part of the "feel" of prior D&D.
Being so wishy washy on explaining some of the effect first mechanics and how that works, etc. Just lay it out -- HP are not meat points, prone is a condition that represents hampering an enemy and usually that can be represented as knocked to the ground but could also...
I find the "creativity/imagination" comment from above very funny, because I found 4e played much much better with players that were creative and imaginative. The kind of players that could make skill challenges work well by reacting to the fiction in a push/pull way, could help wrap a narrative around the occasional mechanics where the default narrative didn't fit perfectly, didn't have a problem using improvised actions which I could easily make worth it using p.42, never thought warlords were shouting wounds closed because they were imaginative enough to think of HPs as partly a narrative device, etc.