"Effective" is defined by me as "not having encouraged an armed revolt against the government" and "efficient" as "has not yet thrown a substantial portion of his staff and cabinet out".
The change in tone IS the effective and efficient. That's the whole point.
He may or may not have promised he wouldn't be a batshit crazy fuckwit. Regardless, he has delivered in spades. That's the only promise I care about. Literally -- the ONLY one. Has that been "transformational"? Of course, because the former guy was a batshit crazy fuckwit.
Has he healed anything? I don't know. Is the divide entirely a worshipping cult of personality or based on deep-seated fears about many other things? It's both. Trump is the Messiah who will save his base from those fears (and fuck over those perceived to be/blamed for causing those fears). As people become unhappier, they gradually move to more singular, broader solutions. Like Trump. Religions have been leveraging the desperation of the unhappy and providing be-all, end-all singular solutions for your every ill for about 2,000 years. Cure-alls, medicine shows, Lourdes, fucking Scientology, etc. etc. I doubt Biden's going to change that.