"...the only way to take the power into your own hands is to become able to adequately defend yourself."

CF is not a skilless game. On average, a newbie is going to get pasted. There's nothing wrong with that, by the way. CF is not a game for those who won't deal with character death; such players will never stick around in any case. It's the meaningless frags that are objectionable.

"And losing will never be fun, no matter how much you sugar coat it."

On the contrary. One time when my character was killed, my killer at least granted me three words describing a faction when asked why. I wasn't ecstatic about losing 1/3 of a con point and a few baubles, but I got something in return: a story element to enrich my roleplay. Hopefully my follow-up roleplay will give other people some enjoyment, too. RP makes anything more fun.

"No amount of Immortal policing can replace that as the best defense mechanism against Quake-style players."

As mentioned, newbies can't miraculously win every such fight, just as immortals can't miraculously intervene in every situation. It's no more fair to blame the newbies than to blame the immortals. How about blaming the people who can't spare three words of RP? High community standards for roleplay are the best control we're likely to see. (And with so much emphasis on grouping for leveling, community opinion isn't something to sneeze at. I'm sure that's one reason RPlessness is less of a problem at higher levels!)