I never loved friends the way a lot of people did but I thought he was really good and showed himself to be a proper actor in various guest roles in more heavyweight tv. West Wing, The Good Wife, Scrubs, The Good Fight - I’m sure there’s loads more on shows I didn’t watch.
The most tragic thing is how inevitable it feels that he was going to die young, it seemed he only made it into the press because he was looking terrible or had some sort of run in with the law while high. I heard on the news he had 15 attempts at rehab, and nearly died 2 years ago and 4 years ago.