Aren't you concerned if DCS went under you'd lose all your $$ invested planes/terrains?
Well, you're the one who brought up DCS...
Not at all. Companies don't go out of business overnight without warning. To avoid legal entanglements the ED would simply disable the DRM in a patch on the way out the door.
If not, then I'm sure any bankruptcy court would order that as part of the orderly liquidation of assets.
And if not, as this owners previous sim learned, DRM is trivially easy to defeat. There issue isn't a technical one, it's a legal one. With no company left to seek recourse, a DRM hack would appear on the web within days.
In fact, DCS would be a lot more resilient to continuing after the parent company going out of business than AH. DCS doesn't require a single company run a monolithic server. It is distributed and non-centralized already.
But given DCS has no credible competitors in it's space, it's not a concern I'd give much time on. Odds of a asteroid strike, Carrington Event, or Yellowstone Caldera eruption are probably higher.