There's a weird gap in that lineup in that practically every person on that list is pretty old (born in the 30s-40s) and their achievements usually date from around the 70s.

Is this just because achievements are usually recognized in retrospect, or is this because the 50s to 70s were the most influential portion of computer science (since all groundbreaking things were discovered in the beginning), or is this because women were pushed out more and more by the 70s?