You
can land anywhere on a planet surface, it was shown clearly in the direct showcase. As you click on a planet surface from orbit you create a marker...you can then enter the landing cutscene and drop the ship on that marker. Some of the planets already have fixed POI's, settlements or mission markers which have their own landing zones, each sparking off the auto-landing animation sequence we've all seen a bazillion times if you select them.
Just before setting off one of the first landing sequences shown in SF direct at the main city, Todd '16 times the detail' Howard clearly said in commentary. "You can chose to land anywhere, but in this instance we're landing at (whatever the city was called)". No, I'm not timestamping the video, do it yourself...I was paying attention the first time
There's no mystery or argument here, it's been mentioned ad nauseum by a variety of Bethesda devs even before SF direct was ever aired that the ability to land anywhere on a planet was a thing...what wasn't there was the ability to physically fly your ship from space to landing zone which seems to be confusing folks somewhat by mixing the two separate events together and assuming.
What happens once you select the landing zone...the game engine draws in a 16km square tile relevant to the planets biome with proc gen flora and fauna to suit. As the player explores on foot, sometimes hand placed assets or events will spawn (that's not an assertion that a player can't walk completely around a planet should they chose to)...or another proc gen scenario like the deserted mine thing we were shown...it's what proc gen is all about.