Games made for the purpose of education are titled "edu-tainment", with the idea being they are fun to play and will educate as you do so.
Of course games don't have to be fun. We all knew that before 30 flights and Dear Ester. If he really wanted a good example of the last year of a great game that wasn't fun he would've picked The Walking Dead. Great game, not very fun, not going to cheer you up.