Changing the CR model to make it more accurate and able to do 1-2 encounters per day would be a big change within the context of 5, and a much needed one, but not really a sea change. Dungeon crawling procedures are
already atrophied in wotc editions and adventures. And arguably point to the success of trad style gaming from the 80s on, so not really anything new.
Not having auto-combat situations is a hallmark tenant of the OSR and recalls some of the earliest traditions in the hobby. PCs negotiating between multiple factions is evident in
Jennell Jaquays's megadungeon designs, for example. So this wouldn't be a sea change, but more of a return to form (and one already revisited in a decade's worth of osr products).
As is often the case, the play styles that appear to be new were there from the earliest days of the hobby.