The only place where a Cobra MKV owner could be considered to have an advantage would be in PvP... and that's not the case either. Would a Cobra MKV have a significant advantage against a Krait MK II in combat with equally experienced commanders at the controls? I don't think so.
Early access to ships has a single goal: to raise funding to continue developing the game. And while the new ships have obvious advantages, these advantages aren't decisive; they only make the life of the commander who controls them more comfortable, but they don't allow them to do anything they couldn't do before, providing that convenience and variety.
Is this tactic ethically reprehensible? I don't think so. And Fdev's good faith in not keeping them in early access indefinitely, releasing them in a few months so all commanders can purchase them with credits, definitively destroys the perverse concept of P2W, since you don't gain anything significant by buying them, except the pleasure of flying them.
If we want the game to develop and not die of starvation, we have to loosen our purse strings a little... or not, if it's your decision to wait, which is as right as contributing by paying for early access.