Locked objects should not highlight at all when drag selecting over them
That’s the whole reason I lock them, so they’re not in the way and are ignored during complex selections. Highlighting them when mousing over? It goes against the very design principle of locking. So annoying to see these fundamental usability regressions at every turn with .ai lately.
Carl, they won’t if you go to Preferences > Selection & Anchor Display and untick Select & Unlock objects on canvas.
And many users actually asked for this feature, you are just not one of them.