Agreed with both points, in different ways.
None of these "bigs" today are messing with Charles Oakley or Barkley or any of the other monsters mentioned ... but then again, I don't think Mark Eaton was going to be able to guard Joel Embiid or KAT or AD on the perimeter. It's a different game for sure.
My overall point about the generational differences in athleticism is that it's so far overblown, both in terms of how much more athletic guys are now AND how much of a difference athleticism makes.
A super good player with elite athleticism ends up being Lebron, MJ, insert name here. But I know just as many Gerald Greens that would get absolutely smoked by Larry Bird, Reggie Miller, Klay Thompson, just to name some random guys that aren't super athletic but know how to play.
I hate to sound like "old man yelling at cloud" particularly because I'm not even very old, but the difference in a very athletic, average player and a below average guy who can shoot, pass and knows how to play is HUGE, and not in favor of the athletic dude.
Athleticism is overrated in basketball, long story short.