He passed the buck to himself...but that buck was stolen from him.
I happen to think Trump was waiting to his second term to undertake this "mess." I don't KNOW that for sure, no one, not even his harshest critics, have tried to make that case. None of his supporters who should know, have either. It is just speculation on my part....BUT! I think that was his intention. And waiting till a second term would be motivated by political concerns/reasons. I freely acknowledge that.
That said, I also think (and really mostly KNOW) Trump would have had a very strong plan in place whereby our military would have been authorized to go on seek and destroy missions. The Taliban would NOT have been able to pile into their convoys of silly pickup trucks and invade all those places they have now taken over. The first group that tried would have been toast and the rest would have stayed hidden in their caves. Today, there would be no problems in Kabul or at any other of the major cities and we would be seeing a VERY orderly withdrawal of American civilians and those Afghans who assisted us.
Trump did this very thing in Syria and Iraq when he took office. Mostly he simply stepped aside and allowed our military leaders on the ground to do what they had to to defeat ISIS. Actually, although it would be very messy, more costly in terms of lost military lives and especially civilians, Biden could still order our military to clean up his mess. The Taliban would hide behind human shields, they would indiscriminately attack groups of civilians, and yes, now, there would be a lot of collateral damage. But! after a few days the surviving Taliban would tuck their tails and run. And then we'd be better able to evacuate those needing to get out.
Point is, while I think there would be some "mess" no matter who was POTUS, Trump and others, like Reagan, would have met secretly with our military leaders and set up a plan. Biden is a walking cluster-f - - k.