Looking a little beyond big names (or lack thereof). Here's every Defenseman, listed by year and career GP, that played at least 350 NHL regular season games born between 1975-1982.
1975:
Bryan McCabe
Kimmo Timonen
Hal Gill
Brendan Witt
Francois Bouillon
Janne Niinimaa
Marek Malik
Andy Sutton
Jason Strudwick
Niclas Wallin
Nolan Pratt
Andreas Lilja
Anders Eriksson
Shane Hnidy
Stanislav Neckar
Jamie Rivers
Yannick Tremblay
Jamie Allison
1976:
Ed Jovanovski
Dan Boyle
Mattias Ohlund
Lubomir Visnovsky
Mathieu Dandenault
Filip Kuba
Bryce Salvador
Sheldon Souray
Kim Johnsson
Rhett Warener
Oleg Tverdovsky
Brett Clark
Brad Lukowich
Denis Gauthier
Wade Belak
Danil Markov
Radek Martinek
Deron Quint
Radoslav Suchy
Sean Brown
Pavel Trnka
Daniel Tjarnqvist
1977:
Zdeno Chara
Wade Redden
Pavel Kubina
Stephane Robidas
Willie Mitchell
Toni Lydman
Marek Zidlicky
Tom Poti
Jay McKee
Colin White
Mark Streit
Kyle McLaren
Joe Corvo
Brent Sopel
Mark Eaton
Bryan Berard
Aki-Petteri Berg
Brian Pothier
1978:
Chris Phillips
Derek Morris
Andrei Markov
Tomas Kaberle
Cory Sarich
Michal Rozsival
Rob Scuderi
Mike Weaver
Jan Hejda
Andrei Zyusin
Ben Clymer
1979:
Brian Campbell
Brad Stuart
Scott Hannan
Eric Brewer
Andrew Ference
Martin Skoula
Paul Mara
Henrik Tallinder
Nicholas Boynton
Steve Montador
Mike Commodore
Karel Rachunek
Mike Van Ryn
1980:
Robyn Regehr
Brooks Orpik
Francois Beauchemin
John-Michael Liles
Bryan Allen
Jordan Leopold
Vitaly Vishnevski
Dmitri Kalinin
Doug Murray
Greg Zanon
John Erskine
Marc-Andre Bergeron
Ossi Vaananen
Jim Vandermeer
David Tanabe
Sheldon Brookbank
1981:
Ron Hainsey
Niklas Kronwall
Barret Jackman
Paul Martin
Dennis Seidenberg
Johnny Oduya
Kevin Bieksa
Andrew Alberts
Garnet Exelby
Kurtis Foster
Randy Jones
Kurt Sauer
1982:
Dan Hamhuis
Nick Schultz
Andy Greene
Christian Ehrhoff
Zbynek Michalek
Anton Volchenkov
Deryk Engelland
Rotislav Klesla
Keith Ballard
Mike Komisarek
Shaone Morrison
Brett Lebda
Jay Harrison
So they'd be aged 25 (if born in 1982) through 32 (if born in 1975) in 2007-08, which I think would be the year that best captures the Defensemen prime of that extended group.
Norris Voting that year had 4 of the top 10 be just a bit older than the oldest in that group, Gonchar (1974), Pronger (1974), Rafalski (1973), Niedermayer (1973) so not necessarily dinosaurs. The winner Lidstrom (1970) was a lot older than one would expect. Phaneuf (1985) and Green (1985) were quite young, fueled by their points yet neither would be considered of particular renown by the time they were done. And then Chara, Campell and Markov were in range.
If my count is correct then I think 56 Defensemen out of the top 100 Defensemen in terms of ATOI were in those birth years. I'm not sure if there's a different year (probably immediately before or after) that would have a wider proportion, or how that would look (although I imagine not favorably for them) compared to other year.