I'm interested in knowing your Center defensive ranking scale.
Many on here - including myself - would classify Pierce as being a good defender - even Elite at times as he got older - but he never got any Defensive Team votes.
If I'm not mistaken - every C you mentioned up there is AT LEAST 2nd team defensive.
As for my Center defensive ranking scale, that would require me giving you my password to my top secret EXCEL spreadsheet with all my intricate formulas in it... You can't possibly think I'm that crazy!

I just think those guys in my Tier 1 all quite clearly had more dominant effects at times in their career than Ewing did.
Hakeem - shut down Ewing and D-Rob in playoff series
Walton - incredible help defense swatting many of Dr J's layups in nba finals (was also first-team all-def)
Russell - no comment needed
- 4x DPOY
Robinson - DPOY, 4x first-team all-defense (and some more second-teams too)
Kareem - 5x first-team all-defense, 4x block champion
Ewing comes
nowhere near those accolades or accomplishments, ever. Even Willis Reed who I later pulled off was 70 and 73 Finals MVPs matched up against Wilt. I don't know of a single postseason series when Ewing "shut a guy down" that was, say, a player already drafted in this game or played amazing help defense that influenced the outcome of a series. I don't know of any players that speak of Ewing as a defender they hated to go up against. (I even googled it and couldn't find one)
Nobody has even posted one accomplishment yet for Ewing except for "all-league" (second team). I just hear "he was very good". But he got obliterated by Hakeem in the finals and by MJ whenever they met. Sure, those are two all-time greats... but they are also on 2 of the 11 teams in this league of all-time greats. I get the feeling that all the guys in this game who Ewing didn't get to go up against would also have absolutely zero fear of Ewing's defense and handled it similarly.
I'm still open to being convinced that he belongs at the top of the bottom 6 defensive centers in this game... but it has to be with more than just "he was a great defender".