I think the issue is that a little complexity adds a decent amount of TIME to resolve. One of the primary goals of this edition appears to be trying to change the average combat time back to what it was in 1e or 2e(i.e. 15-20 minutes).
. . .
If you start adding in a bunch of abilities that modify the battlefield and add modifiers to people, it takes time to adjudicate those and increases combat time.
Having GM'd a 12 session of Champions that was just one single fight - which did not finish at the end (we just gave up and said: Ok, those 4 guys just up and fall down, its over)...
The more tactical the game gets, the more variety, the longer it can take to resolve. And this can get monstrous.
Sadly this is a BIG sacrifice though. The lack of all those tactical options can make a game feel amazingly bland... and old D&D was horridly bland in play compared to old Champions or Fantasy Hero or even Runequest.
You don't need the tactical complexity of Hero system, but that doesn't mean going all the way to the other extreme and just rolling a d20 and a d8 and then tallying down a number before moving to the next guy...
Much as 4E can frustrate some of us, one of its design goals was right: A lot of players now are coming in from computer games and online games where they are used to a certain pace and a series of options on choices made quickly within that pace.
If I can find more enjoyment tanking a night of Dragon Soul in WoW, despite doing it over and over again every week, than from playing out a deep story RPG with a combat scene now and then... then there's a problem somewhere in the design of that RPG.
Blanding down the mechanics in the interests of time is a viable plan - but you've got to be careful not to go too far... either way...