What I really enjoy about One Day at a Time is how the writers set thorny issues in context so as to make us ponder on their impact in today's society. Ranging from racial discrimination to depression, over the last few seasons there have been an increasingly reinforcement of more serious topics.
Personally speaking, taking into account not only the current social relevance of such issues, but also the outstanding performances put on by the youngest actors, I would point sexual descrimination and alcoholism as the standouts of this year's season. Following an art-imitates-life schema, the scene in which Elena and Sid are almost attacked by a group of men resembles the real-life case of a London lesbian couple beaten up in the train station earlier this year. Schineider's alcohol relapse near the end of the season could be considered one of the saddest moments of the whole series so far.
Though the approach to these topics does not outweigh the amount of laughs we get from the show, it makes it feel less like a sitcom and more like real-life drama. In no way it diminishes the value of the season, but I would definitely say that I spent more time reflecting on what was being depicted than laughing. Despite not being my favourite season thus far, it has surely been the one that made me think the most.