Re: 1v1 - Kobe Bryant v. Larry Bird
At both their primes, both wouldn't be able to guard the other.
When Jordan tried to guard Bird, Larry murdered him in the post, or just shot over him like it was nothing. Same would happen to Kobe.
Larry didn't have the lateral quickness to guard Kobe on the perimeter, he would just need to rely on sagging off and protecting the basket or do some ball stealing and blocking like he used to.