Well if you believe those players are better than the ones I mentioned, I don't know what to say. Again, it's just a theory but I also have to call into question just how good Charlotte, Washington, Detroit and Miami were at being very good 5-8 seeds. Did any even win 50 games? I don't think so.
Just a theory and if others want to try to prove or disprove, go ahead, but I think a lot of it might be that most of the top 20 players or so play out West and have for a while. So you see the dynasties: San Antonio, LAL and GSW but a lot of top talent were on teams that had one top player that made the team really good but not a contender likeI don't know.
Dame in Portland
Westbrook in OKC
KG in Minny
Griffen in LA
Harden in Houston
Paul in New Orleans
Hayward in Utah
Dirk in Dallas
Gasol in Memphis
My theory is besides having the dynasties, they had more teams led by superstars so the 3-10 teams out west were just better because they had the better top level star to lead the team.
George or Oladipo in Indiana
Wall AND Beal in Washington
Wade in Miami (pre and post James)
DeRozan AND Lowry in Toronto
Horford AND Milsap in Atlanta
Walker in Charlotte
Anthony AND Porzingis in New York
Rose or Butler in Chicago
IT4 in Boston
Drummond in Detroit
I mean it isn't that hard to do the same thing in the Eastern Conference.
The reality is, the western teams really have just done better at drafting. I posted the draft spots of the last several All NBA Teams and they predominately reside in the West, but the gap has steadily been closing, which I expect to continue as the vast majority of the top end young players are currently on Eastern Conference squads.
I'm confused when did OKC win 50 games (I mean sure with Durant they did). Portland won 50 twice, but with Aldridge as well as Lillard (in other words they haven't won 50 in years). The Clippers weren't a 50 win team until they had both Griffin and Paul (so you can't count Griffin in LA and Paul in New Orleans). New Orleans did hit 50 once with Paul (along with West, Chandler, and Peja). Utah also hit 50 once but was only over .500 one other time with Hayward (43-39). And if you include KG in Minnesota, then Wade in Miami (post-title pre-James), Bosh in Toronto, Iverson in Philadelphia, Howard in Orlando, etc. are on that list. That is one of the problems with your list, there is no rational relation to time-period. It is also strange to include Griffin in LA, when he was there for like half a season without Paul (who you included in New Orleans, which was basically a decade ago at this point). Westbrook had only 1 season without another top 10ish player on the roster. Drawing the line at 50 wins is also strange since there is almost no practical difference between the Wizards winning 49 and a playoff series led by an All NBA 3rd teamer (Wall) vs. Utah winning 51 and a playoff series and led by an All NBA 2nd Teamer (of course that was Gobert and not Hayward). Or the 48 win 2nd round Heat. Then you have Dirk, who hasn't been on a team winning a playoff series since they won the title in 2011 (which pretty much correlates to the last time Dirk was a top tier player - Dirk was 2nd Team All NBA that year, 3rd Team the next year, and hasn't been close since). Why not include Kobe on that list, or are the Lakers excluded because they were a true contender? Ah but see if you do that, then Dirk shouldn't be on there since Dallas hasn't been any good since they were an actual contender. Of course you included Harden and his absolutely true contender Rockets in there, so again I'm confused as to why certain players were chosen and others were not.
And for the record Paul George has been on 4 All NBA Teams. That would be the same as Griffin, but more than Lillard, more than Gasol, and more than Hayward who has never been on an All NBA Team (making him basically Kemba Walker, but with Rudy Gobert). Rose was a MVP of the league. Butler has been on 2 All NBA Teams, but 4 All Defense Teams. Even Drummond cracked an All NBA 3rd Team once. So yeah, taking the MVP's you mentioned out of it (which as indicated above seems a bit strange), yeah I'd take those guys from the East vs. those guys from the West.