My qualm with registrations is that you can register and still be a "lolwutting capwhore". Being able to type a paragraph of RP on a forum post doesn't necessarily make you a better player. Case in point - the Order. Some of the "good ones" break rules and have poor RP, like "Leave minor now" as they fire two missiles towards a bomber.
Also, registration has nothing to do with killing light fighters. If I buy a Red Hessian Cruiser and don't notify the RHA, then it doesn't mean I'm going to go around hunting Phantoms with it. It just means I didn't want / feel the need to register (hypothetical, in practice I would simply as I'm in the faction).
Also, people may have issues that there are no fighter registrations - there are only ones to register capital ships. The reason why "capwhoring" is a "major problem" is because the majority of players here fly fighters and bombers. To them, a lolwutting fighter indie is nothing but free bots and bats. A capital ship on the other hand, requires effort to kill. I prefer being attacked by a capital ship indie with no engagement notice than a "good RP" fighter/bomber with a set msg engagement. At least I can escape the capital ship.