It is, simply, sublime. It is brilliantly written, brillantly acted, and brilliantly directed. It is like watching a wonderful play, but on-screen. (I don't go to enough plays -- I am always surprised, when I come out, at the experience.)
It might not really make sense to younger people. The 1980s were a unique time with the start of the worst pandemic in history (that's right -- in history), and the Reagan Administration's despicable handling of the situation (which basically amounted to completely ignoring it).
If you haven't seen this, I recommend that you rent it. Every performance in it is great -- and most actors play more than one part. You won't believe Meryl Streep in one of them.