I mean, yeah?
Of course you can't convert your save file where you could have save scummed, TPK'd multiple times and cheesed through bosses into a difficulty setting that specifically locks you into no loading saves to ensure you don't save scum your way through the mode.
At best, I could see them putting in the additional boss power into the Custom Mode options (As that's the only thing missing from Custom Mode, which would allow you to simply recreate Honour Mode without the reward from completing a playthrough on Honour Mode. You could even make a harder version of Honour Mode with the additonal settings that hide features of the game)
+1 to this, I'm confused if it's supposed to be a challenge run why people would assume the wouldn't have to restart on a different playthrough?
Would be cool to see legendary actions added to Custom mode but other than that, I can't honestly say that the concerns here were entirely realistic...
