But my preferred style is to run games like I like to run them. And from what I can gather, that's making it hard to find enough DMs. My understanding is that finding DMs was hard enough already. And honestly, I don't now what WoTC could do to make it easier. They are already giving a bunch of perks to DMs. It's just the nature of the beast I guess.
It's true, I think, that GMs, in general, have perennially been hard to find - it's been a truism of gaming, because GMing is just a /lot/ more work than playing. It's a bit less true of D&D, if only because so many people have become so familiar with it over the decades, so DMs are hard to find, but if you're used to how hard it is to find a GM for some other game you like, really not /that/ difficult.
However, at my FLGS, we've never had trouble getting enough DMs for Encounters. Encounters started with 4e and continued through Essentials, and both those versions of D&D were really quite easy to run. So, while an old-timer wedded to the sandbox style might not be too attracted to the program, those willing/able to run in the more directive style demanded by organized play were common enough. (Actually, even though one of our regular DMs really prefers sandboxing, he's just willing to run organized play, as well.) But, the main thing was that some new players would fairly quickly start DMing, as well. We started with (relative) old-timers running, but now we have 6 or 8 folks willing to DM, and only 3 of them have gaming histories going all the way back to the 20th century. Most started with 4e and learned to DM with it, which, like I said, is pretty easy. So far, only the three more experienced DMs (myself included) are up for running 5e, but I suspect that will change as the others get some experience with the system.