JEB
Legend
What I foresee is the further watering down of race beyond what Pathfinders ancestry has done: a couple of physical traits like size, speed, vision and a unique ability like fey ancestry or poison resist. Everything else handled by some background/subrace -like mechanic that is interswappable and grants proficiencies, cantrips, and languages. It will be set up so that you can take other races as well to represent an orc raised in Cormyr or a human who lives among the shield dwarves. As a side-effect, the half-races and planetouched could live here rather than as base races.
The downside, of course, is some races would need major reworking as they are either all biological abilities (dragonborn) or mostly cultural (halflings). You are also marrying race far deeper to setting as generic versions of elves and orcs are replaced by region-specific options, but this is all something for the 6e team to figure out.
I can see something like this, but I suspect there's still going to have to be some default expectations for character races (or people, folk, or whatever other term they decide on), similar to how they have default suggestions for character classes now. If the game doesn't have those, it could actually become less friendly to casual players, who can't just create (for example) a Gimli or Legolas clone without sorting through unfamiliar subrace/culture/background choices. (And let's not forget, the majority of players are casual.)
Which isn't to say I don't support such a flexible approach to character creation; for example, we'd presumably get alternate core cultures for dragonborn, tieflings, and other currently monoculture races, and that'd be neat. But I think it'll need to be default + alternate options to remain new-player-friendly.