You could call it “pay to progress” I suppose, but there’s a couple things to consider.
(1) Gaining access to better equipment and more skills does not automatically guarantee that you’ll win more fights. Success, especially in solo/small-gang PvP, depends heavily upon preparation, target selection, and actual piloting skill. Youtube is chock-full of videos of players using their game knowledge to fight and win in situations where their death seemed all but inevitable.
(2) This is a game where you can log in multiple subscribed accounts to enhance your gameplay. If you consider PLEX and injectors to be sliding towards the pay2win side of things, then character trading via the Character Bazaar, and the ability to log in multiple characters simultaneously must also be considered pay2win.
(3) EVE has no win condition (other than escaping it). You can pay to advance towards whatever goal you have chosen to pursue, but there’s no real “winning” here.
Whether or not injectors are good for the game is a matter of some debate. They almost certainly brought back a number of players, but they also allow the playerbase to min/max every change that CCP makes at a much faster rate. This likely means that CCP has to slow down development and be very careful with each change they consider.