Here is what I think:
I recall there being licensing issues with Fallout's GECK and we almost didn't get it. So, since this engine is built in-house, completely by Bethesda, there shouldn't be any licensing issues with the CS itself, though it may be restricted with third party software (Speed Tree, etc.) as it was for Oblivion. But hopefully they've learned and can actually give us a functioning piece of software so people can adequately fix any mistakes they've made
And, as has been said, Bethesda is not stupid. They realize that Morrowind wouldn't still be on the shelves without the CS. Neither would Oblivion. Mods expand the shelf life of games, it's a fact. So unless Bethesda plans on shooting themselves in the foot, there should be a CS. Thought it may be more complex than what everyone is used to, depending on this new engine.