Brent Spiner was 49 in South Park: Bigger, Longer & Uncut when he played the character 'Conan O'Brien (voice)'.
That was over 25 years ago in 1999.
Today he is 75, and has starred in 46 movies in total, 19 of those since South Park: Bigger, Longer & Uncut was released.
In South Park: Bigger, Longer & Uncut, I think Brent Spiner looks: