Well - "new" in this case means "post-crisis." And I'd say plenty. It works okay with Kon-El or Jaime Reyes in their early days, since they are younger, but they definitely have heroes come around to encourage them and tell them they are doing well (or alternately castigate them). Judgement and condemnation got piled on Booster and Huntress by senior heroes. Back when the silver age heroes were heroes, they had team-ups, but they were always peer-to-peer. No training provided, no casting judgement, and most especially no junior-to-senior dynamic. Early post-crisis really drove me crazy with this. They wanted to use established heroes to guest for sales, I guess, but it was extremely frustrating to read new heroes not allowed the space to grow independently and had to receive either validation or confirmation from the senior class. And, as it seems like more and more heroes are legacy now, they are more and more tied to previous "generations" they are more likely to be trained by others than to set manage their own training, more likely to be judged (as good or not), more likely to be funded by others, and overall, IMO, less allowed to be really independent of their mentors. That they even have specific, continually involved mentors, is something that sets them apart. Which wouldn't matter so much if it was only a few, but it certainly feels like a large percentage of the new ones to me. As I said previously (not sure on this thread), a lot of it is the more integrated nature of comics (they didn't mix fandoms as much back when), and that later there were a lot more pre-existing heroes still around and in the same world, but to me I do feel like new heroes don't get the same freedom and independence that old ones did. It's frustrating to me to see a character that got to do things their own way without any interference (Superman, Batman, etc.) come and criticize and try to control new generations because they aren't allowed the same opportunity.