I have discussed an analyzed this this pretty extensively (including on the Sim Hangouts where Scott and Gonzo love their nostalgia goggles).
What people often forget is that beyond the top players, centers in the 80s/90s were BBQ Chicken (which made things easier for the guys who could play). Hakeem used to joke with Kenny Smith that he only had to play 5 times a year while Kenny had to play every single night.
Let's re-wind 20 years. Jordan was out of the league, Robinson won MVP, and Hakeem/Shaq matched in the Finals right after Hakeem/Ewing the previous year. The league even shortened the 3pt line, making centers nigh impossible to double (manufacturing a cinderella run for the Rockets that has never been replicated in any era of NBA history). This was the pinnacle of the dominant center.
EAST
Magic (57): Shaquille O'Neal (28.6 PER), Tree Rollins (7.0 PER)
Knicks (55): Patrick Ewing (21.9 PER), Herb Williams (7.7 PER)
Pacers (52): Rik Smits (19.5 PER), LaSalle Thompson (6.8 PER)
Hornets (50): Alonzo Mourning (20.1 PER), Robert Parish (10.1 PER)
Bulls (47): Will Perdue (16.3 PER), Luc Longley (12.3 PER), Bill Wennington (11.6 PER)
Cavaliers (43): Tyrone Hill (16.8 PER), Michael Cage (13.5 PER)
Hawks (42): Andrew Lang (13.1 PER), Jon Koncak (9.5 PER)
Celtics (35): Eric Montross (12.1 PER), Pervis Ellison (13.3 PER)
Bucks (34): Alton Lister (10.2 PER), Eric Mobley (14.2 PER)
Heat (32): John Salley (11.4 PER), Matt Geiger (12.9 PER)
Nets (30): Benoit Benjamin (13.9 PER), Dwayne Schintzius (6.2 PER)
Pistons (28): Mark West (12.8 PER), Oliver Miller (16.9 PER)
Sixers (24): Shawn Bradley (14.8 PER), Derrick Alston (11.6 PER)
Bullets (21): Gheorghe Muresan (17.4 PER), Kevin Duckworth (9.9 PER)
Out east we can see pretty see that the quality of your big-man was almost directly relative to your team's success - and that most teams simply didn't have one.
WEST
Spurs (62): David Robinson (29.1 PER)
Jazz (60): Felton Spencer (12.3 PER), James Donaldson (7.9 PER)
Suns (59): Joe Kleine (9.8 PER), Danny Schayes (13.2 PER)
Sonics (57): Sam Perkins (16.2 PER), Ervin Johnson (9.6 PER)
Lakers (48): Vlade Divac (20.5 PER), Sam Bowie (10.4 PER)
Rockets (47): Hakeem Olajuwon (26.0 PER)
Blazers (44): Chris Dudley (10.9 PER)
Nuggets (41): Dikembe Mutombo (17.0 PER), Bison Dele (13.9 PER)
Kings (39): Olden Polynice (14.7 PER), Duane Causwell (11.4 PER)
Mavericks (36): Lorenzo Williams (10.3 PER), Roy Tarpley (17.8 PER)
Warriors (26): Rony Seikaly (12.7 PER), Cliff Rozier (11.5 PER), Victor Alexander (12.8 PER)
Wolves (21): Sean Rooks (12.6 PER), Greg Foster (10.3 PER)
Clippers (17): Tony Massenburg (11.7 PER), Eric Riley (14.7 PER)
The west ran more to compensate for it's lack of Cs. It is worth noting that Malone and Barkley were the first great PFs and the beginning of a league-wide transition.
ANECDOTES
Perhaps I remember just how many bad centers there were because I collected basketball cards in the mid-90s. This exercise was a trip down memory lane in that regard.
The reason to use PER is it's measuring production relative to the rest of the league, where 15.0 is the standardized league average.
Only two backup centers in the entire league had a PER > 15 (and we know what happened to Tarpley after this season).
Robinson, Hakeem, and Shaq played so many minutes due to their dominance that they effectively didn't even have backups. Chris Dudley on the other hand didn't have a true backup because the Blazers would slide Buck Williams from PF to C and Cliff Robinson from SF to PF.
BBRef lists P.J. Brown as a C for the Nets but in actuality
he was their starting SF next to Derrick Coleman and Benoit Benjamin. That sums up 90s-era ball in a nutshell. Teams often employed double-PF lineups in what is surely the antithesis to modern NBA ball (big ball, killing your own spacing for a marginal advantage on the boards). Teams NEVER do that now, and often now employ double-SF lineups (made popular by SVG w/ Turkoglu/Lewis in Orlando).
Yinka Dare was drafted 14th overall and played in only 1 game due to how big a project he was. Dare had a 6.2 PER in his four year career and is regarded by some as the worst NBA player of all-time (certainly among those drafted 14th overall). Teams drafted bust centers in the first round with high frequency searching for "the next big thing" which was really akin to just throwing **** at the wall. Drafting stiffs is a practice long-since abandoned as teams properly evaluate big men and what sort of role they should be playing.
Well, to start off, there's a reason the NBA fell away from this big-centric era. A player who changed the NBA landscape forever.
Michael Jordan. People often talk about his 6 championships but rarely mention that he won them without a quality center in an otherwise center dominated era.
How could we be more like Mike? Well, for starters, start running your post ups through players who were great passers and ball handlers (limiting turnovers), who could also hit their FTs. Jordan was effectively a center without any of the weaknesses. Teams began to optimize and value their possessions using a dirty word called "analytics".
Patrick Ewing was a great center, but due to his offensive weaknesses he was never able to crack that elite tier. Building an offense around a player that can't dominate is and was folly... and this is Ewing we're talking about, a HoFer, not a scrub. Teams routinely gave post touches to bigs who weren't any good (even though they were often guarded by foul-prone players who likewise weren't very good).
All of the above is why teams began to favor PFs for their post play. Kevin Garnett, Tim Duncan, Dirk Nowitzki, even Chris Webber and Elton Brand came along and the post center went the way of the dinosaur.
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Now, as far as today's NBA, it is crucial for centers to operate on both ends of the pick and roll, which means footwork, hands, and quickness. Stiffs need not apply. Joakim Noah is a prime example of this.
Bill Russell wasn't an offensive focal point, yet he still lead his team to 11 championships doing all of this. Despite that, Wilt had sexy numbers and influenced the next 30 years of play. Yet there is no arguing which player was more successful in a team scheme (and if anything, I think I've shown modern centers are significantly more effective than what they did on average 20 years ago). NBA centers may not be "super stars" posting gaudy numbers as featured offensive players, but it was only a decade ago we were reading blurbs like "former all-star Jamaal Magloire, now playing for his 5th team".