It's not an exclusive ship. It's a pay2play ship that is still there for the taking. All anyone that joined in Horizons has to do is buy an old copy of Elite Dangerous (pre-horizons), and then they retroactively get "exclusive" access to the Cobra 4. Pretty sure it will eventually be $5 on Steam. Not sure it's worth even 5 pennies though, even when it's empty, it's still a garbage hauler.
I think making it free would be a great idea though. That way there could never be any accusations of pay2win, and then maybe they could finally make it fun to fly.
This is not true. When FD switch to the base game + season pass model, they turned off the Cobra MK IV opportunity.
As a matter of principle: NO.
As a matter of principles: YES.
The very concept of exclusivity is that the quality of an item or experience is supposed to be increased by shutting other people out, even when it is of no practical consequence for owners if it weren't exclusive. I suppose it is a natural human trait so seek exlusivity and to deny things to others, but that doesn't make it right. And marketing using it all the time, everywhere, doesn't make it better; it's one of many shady marketing tactics that abuses human psychology for profit at the expense of those who are literally "excluded".
And specifically in the area of gaming, it has become so rampant that it has become the norm rather the exception that you can't even just go and buy "the game" and have the complete package. From multiple editions one more "deluxe" and exclusive than the other, to preorder-only items or content - have all the nopes, gaming industry.
Also, the Wireframe paintjobs is a cosmetic thing, in a place where there are lots of other good cosmetics to choose from. That is a far cry from denying an entire ship to those who simply arrived too late.