The NFL/NBA have very similar types of athleticism and their athletes actually make physical contact with each other. Again, running in a straight line, jumping straight up, or over hurdles not making physical contact at all, these do not really apply to the athleticism you need in the NBA/NFL as a whole.
You're delusional if you think guys are getting by on "natural" athleticism, they worked HARD for their game and bodies. Don't let their at udes fool you, they may act like whiny bags but that doesn't mean they don't train hard. Players like Lebron, Durant, Griffin, Leonard, Curry, Westbrook, Cousins, etc. have all been training since they were just teenagers while Jordan and the whole Bulls team barely started to receive much of the same training as adults.
Gasol isn't a strong guy? He's 6'11 270+lbs:
I bet you probably don't think Matt Bonner is strong either, even though at his 6'10 240+ frame he would've had superior strength and size over most 80's players. You wouldn't be able to stop Bonner in the 80's, he would've lit most teams up with his shooting ability. He could get whatever shot he wanted.
Lol, look at how things stagnated from '70-80. The first strength and conditioning coaches in the NFL were hired in the early to mid 70's with Marinovich being one of the first. He is heavily responsible for the Raider's '76 championship, the same way Grover was heavily responsible for the Bulls' success in the 90's. As more and more teams started to hire S&C coaches you'll notice that by the 80's players weights would start to increase, just like 90's NBA basketball. I'm not sure when NCAA teams started to employ them, that too would have a big impact.
Strength and conditioning coaches were not employed by the NBA until the 90's, Jordan/Pippen had barely lifted weights for a year or two at the most when they played against Bird. Barkley, Olajuwon, Pippen, Jordan all worked with Grover in the 90's. Jordan-Pippen didn't reach their prime playing weights of 220+ until the late 90's.
Johnson played 32 games due to the lockout and wasn't even starting, he was a backup. He was playing PF, but he did pack on like 20lbs, and again, the game has changed since the 90's, it's been 20 years since '95 lol. Johnson would be brought out on the perimeter, isolated or switched against, and would be completely exposed.
Athletes as a whole are superior when you factor in the talent pool, the amount of youth development programs, and the access to proper diet, weight lifting etc. as well as actually pay attention to their skill sets in relation to their size. They worked on their bodies to allow them to do what they needed them to.
You have 6'7 290lb guys running the 100m near speeds that come close to previously set Olympic records, this is pretty damn common in the NFL and even the NBA. If a guy is as agile as you, can run as fast as you, can move as fast as you laterally, but has 50lbs on you, you're ed. Walker's 100m time was pretty amazing and rare in his time, but it's pretty common in today's NFL, even guys that don't get drafted.
The game has changed dramatically now that it's so perimeter oriented, I can't stress that enough. Players utilize much more lateral movements with all the ball handlers and lack of hand checking, guys are forced to cover more areas of the floor, team defense has changed quite a bit. The farther out on the court you go, the more mobile your players have to be.
The NBA didn't start broadcasting live games on cable until like '84, that's when they marketed the out of their stars, Bird, Johnson, Jordan etc. The NBA was still behind sports like the NFL-MLB-Hockey-Baseball-Tennis-Horse racing-Boxing, etc. it was relatively unpopular in America.
Cable tv put basketball on a world stage in the mid-late 80's, that's when the talent pool started to boom. As tv and cable became more affordable and more common in the US, it was put on for a much bigger audience. That had a ripple effect on the NBA-College basketball-High school bball-youth sports.
Right now there are 5.5 million children playing youth basketball in America honing their games from young ages, receiving private coaching, working on their bodies, honing their skills. That 5.5 million gets filtered down to just 550,000 men's HS basketball players, that 550,000 then gets filtered down to the 4,500 Div. 1 basketball players. That is not counting the international pool, you have players from Australia, Argentina, Brazil, Africa, France, Germany, Lithuania, Russia, China etc.
Players like Manute Bol's son are all over the place, I bet if you saw him playing in the 80's you'd think he was a superstar lol:
Whatever a player is capable of doing is relative to the compe ion around them.
Compare Sabonis and Marjanovic in the Euroleague to each other, keep in mind Marjanovich's compe ion is much better. Can you really say Sabonis is a better player than a guy like Marjanovich? Marjanovich wasn't getting burned by the great Niko Gallis either lol.