Friends is great, but still pretty advanced as English learning goes, with fast speech, and lots of slang and US/90s specific references.

I guess so but it also has slower lines too especially for comedic delivery. The cultural references are good (now dated because Friends is 20-30 years old) because after learning a language, cultural references are next when it comes to fully being able to converse

But it's also highly visual. I forget where I saw it, but someone showed people an episode of Friends without any audio, and they could still understand the plot based on the overly dramatized physical communication.