Looking at the wiki, new level-up perks are added, but they're all lower level perks, around the 1-12 range in general. To be honest, looking that FO3 with perks like Grim Reaper's Sprint, then Broken Steel adding stuff like Almost Perfect and Nuclear Anomaly, it's probably better that newer perks don't get any too much more powerful than the current high level perks. And I also doubt that they could add enough 30+ perks to fill the 30-35 range in a way that fills enough playstyles, which is probably why they went back to early levels to fill them in more instead