I Don't know about everybody else but I've been clear about the point that neither TSR nor WOTC has made a clear description of what high level is except in for fourth edition.
I've stated several times that WOTC did not pay attention to high level other that creating Archmage NPCs like Elminster,
And the key is to make the decision, stop punking out like a bunch of babies, and raise or lower the power of warriors, experts, priest, mages, spells, weapons, hit points, and maneuvers to match.
"Wah. We might upset some players"
Those players don't want to play high level.
You're talking past me again.