Totally.
But there's no shortage of retro-clones and D&D-like games. Anyone can make a D&D-esque game. But only D&D can provide everything else.
The biggest problem with those variants is finding a steady group to play them with. There's a critical mass you need to make a system viable. 3.5 / PF / 4.0 are all viable due to the numbers of people still playing them. But although I had a harder time finding DDN Encounters sessions, I did find one, and I think it will destroy the other editions. It's not perfect, but it's loads faster to play and pick up than 4e or PF, you can do so much more than 4e with even the limited spells you have (.e.g. my ranger can move some distance, attack a couple times with a maneuver and maybe even a swift heal), then jump over the table and tumble down the exit in one round. In 4e that would have required me several magic items, some multiclass feats, a daily, an encounter power, and an action point. This game feels more cinematic and also plays faster too. I think it will win.
Only competition would be PF 2.0, but is there any news on that? If so, could you post a link? I'm curious. After D&D Encounters moved up to D&D Next and the 4e support goes down, it will only be a short while before most people jump on board. It's in a very early state but is already much more playable and feels like a proper D&D experience to me. It even has difficulty / survivatiliby dials. We were playing on the dials way high (max hit die every level), which I would have rather not had, but anyway. If I were DMing, I'd much rather build something quick n dirty with DDN then flesh out the world as it gets released, than build something entirely in another system. There are still major bugs to solve but it's got the name, it's got the feel, it's got the flavor, it's got the ability to run tons of encounters in a couple hours with a lot of people at the table, each not taking 10 minutes for their turn. I mean, it was our first game and we did I think 5 battles and tons of RP in under three hours. Had a lot of fun, and looking forward to playing it every week.