Turning down the role of Margaret Thatcher in The Iron Lady. The part went to Meryl Streep, who won an Oscar.
Turning down the role of Katharine Graham in The Post. The part went to Meryl Streep, who won an Oscar.
Turning down the role of Princess Diana in The Crown. The part went to Emma Corrin, who won a Golden Globe.
It's hard to say whether Streep would have won Oscars for all of these roles, but there's no doubt that they were all iconic and could have further cemented her legacy as one of the greatest actresses of all time.