Just to be clear: problematic means that something needs to be discussed.

Friends was made during a time when sensibilities were different.

Some subject matters would have been addressed in a different way if the show was made today.

Acknowledging that, doesn't mean that the show is terrible.

Also, many sitcoms suffer from the same problems: over time, characters become caricatures and act in ways that in real life would make them extremely unpleasant.

The reason I like Seinfeld is that the show always acknowledged that the characters are not very good people, whereas Friends is less self-aware.