It's kind of a chained question pair though. "what does that look like" can't be answered without answering or assuming the design goals @Benjamin Olson brought up in #4 because he's right about it seeming random so far & the lack of focus design by committee or worse. That lack of focus is how we get 5e style design for nobody & everybody with the gm left holding the bag to make it work when the system itself fails to be about doing anything well out of fear that somebody might not like that thing.Not really the spirit of the thread.
What concrete design directions could they employ to create a distinct new edition that would still feel like D&D?
Personally I kinda hope that 6e is meaningfully different from 5e & felt that way long before the whole OGL debacle. I'm already trying to move away from 5e & eagerly awaiting options on the near horizon before deciding what to do about my current holding pattern. Bare minimum I'll probably give it a glance but what I do from there depends on the goals they aim for.
Different for the sake of being different is just exhausting if I need to convince my players that 6e is designed for xyz goals in order to begin making a case fir why we need a given houserule for the campaign. I've had that for the last several years & not interested in a rehash of that brick wall.