One way to slow down and/or curb some power levelling -> put a cap on the number of levels that can be obtained per hour/day (just throwing it out there, not for discussion or to be told how foolish I am)
I mainly play on Excelsior, so I cant really speak on the other servers.
I have run across some 50's that had no idea what they were doing. How to travel. What their own powers did or were capable of. I even came across a 50 that had no enhancements at all.
However, it is not very often.
Would I like a level to be a true indication of their experiences? yes, of course. The other day, I saw a toon that was less than 45 days old, with a veteran level over 200. All I did was shake my head, and move along.
This issue is not ruining the game, or even my enjoyment of the game.
It means nothing. Just like forum post count is not an indication of knowledge, or insight.