What does a limit on buying currency keep it from being Pay-to-Win?

You're buying currency.

You have not played through the game to achieve the currency. You have not subjected yourself to the chance of deaths, ganks, and the being able to fail at acquiring the currency through things like making a bad trade. You have opened your wallet and you have advanced in acquisition of an in game asset due to the wallet. You have paid to win at moving through the title without consequence even if it for a small amount of the title.

This applies to the ship purchases as well. CIG could have made it so that you get blueprints to build a specific ship instead of just handing it to you. They could have still had the hangar module so you could see your purchase, but then make it so you have to actually play through the game and make the ship.

Stop this nonsense about not being pay to win. Boosters, buying items, temp buff...etc. You're paying to win. You have not achieved the items through playing the game. They were handed to you because of cash. It's a simple binary question. Was this advantage bought with cash? YES/NO. It doesn't matter that every developer is doing it. It's still paying to skip ahead without subjecting yourself to playing the game. This instant gratification for cash because people don't want to put time is getting ridiculous.