that's BS though because that's exactly what I did. except as soon as you hit dz10 then everything requires dz30. So you can either play light zone and lvl up to 30 and get the same level gear that you would off the elites in the DZ from doing missions and stuff, or you can waste a bunch of time ranking up to dz 30 before you hit lvl cap.
Going to dz early once you hit lvl 10 is smart. extract a bunch, grind to dz 10, buy dz loot. then only go back if you have a group or if you want to try your luck at maybe getting a lucky drop but it's probably more efficient to just run missions anyway.