But, beyond that, can't we give Matt Weiner the benefit of the doubt in assuming that this was a deliberate choice with no malicious intent? The series begins in March of 1960, it's more 50's than 60's. By season 6 we're into 1968, SCDP has a woman partner, no one bats an eye at a woman on Don's creative team, Roger has married -and divorced- a Jewish woman, and Don has an African American secretary. These are great changes, and remarkable when one goes back to watch the early episodes, but they wouldn't have been nearly so significant if Matt Weiner had chosen to portray the office as more diverse from the start.
This. Definitely this. The gradual changes have added up to several differences between the way things were at the beginning of the series and how they are now.
There can be no question that 1968 was better than 1960. Do they still have a long way to go? Absolutely. But when you think about it, so do we as a people in 2013.
It should also be noted that Matt Weiner himself is Jewish and has several women on his writing staff.