I hear you but the #1 Wizard on the EU leaderboard is using this setup.
http://eu.battle.net/d3/en/profile/Simba-2186/hero/47364702
That's solo GR40.
Are you sure that is his grift gear? Looks like T6/lower grift farming gear. His follower is literally built for Bane of the Trapped abuse, but he's using Bane of the Powerful, which is worse than trapped in higher grift levels because it doesn't do anything vs. the rift guardian, but is superb in T6 rifts and lower range grifts. If he was just running T6, Maximus might be the best weapon for that difficultly because the fire chains are relevant and usable (which they more or less aren't at grift 34 or so and above) and he doesn't need the extra damage vs. elites at that difficultly since they die to fast to his dps already.
Also, he's using pinpoint armor instead of Force Armor on the Energy Armor rune, not running Unstable Anomaly, and at the same time as those not using a String of Ears. That loadout is actually going to die to white mob melee in a heartbeat in grift 40.
99% sure that's not his grift gear. The reason why a superb SK+source (note the word superb there, a bad SK is still bad) is slightly better than Maximus on higher grifts (I've tested both) is that for the way you play, elite kill time is everything. White mobs die as a side effect of the big AoE damage you produce while killing elites, and you more or less herd white mobs around behind you until you get to the next elite pack, kill everything, then keep moving.