Indeed. But you have no evidence that it will take the form of tangible game content. Could well just be cosmetics and frankly, that's harmless. Last I checked a paintjob or ship kit doesn't provide an entire unique spaceship in a spaceship collecting game with unique stats. It just changes the thing's colour.
And no, I really doubt it would be detrimental. Most of the gaming community, not just in Elite but across the board, is sick of exclusives. They are almost up there with loot crates, quite honestly, in negative opinion.
Plus as I have said so many times, exclusives in many, many other games have been made available to the masses later down the line for years, across the whole industry. It's not a new concept and nobody outside this playerbase would bat an eye, as it's far from unusual as a practice by game devs.