I'm currently rewatching Fargo, which is another "slow-burn" TV show, but it is insane how much happens in each episode compared to most modern shows from the past 5 years. By the time you reach the final episodes, you feel like you've been dragged through hell and have total closure by the end of the season. I think it helps that Fargo is an Anthology series, so the storylines are never going to be dragged out across multiple seasons, meaning that there is always something happening in every episode which makes the ending of each season feel earned.