Josh Brolin was 46 in Avengers: Age of Ultron when he played the character 'Thanos (uncredited)'.
That was over 9 years ago in 2015.
Today he is 56, and has starred in 71 movies in total, 18 of those since Avengers: Age of Ultron was released.
In Avengers: Age of Ultron, I think Josh Brolin looks: