The cynicism and story of the abrupt end of the comic, leaves an ambiguous hole in the story of Calvin. Those next stages of dialogue, that a child such as he must go through to continue. The author's hermiting, who is Calvin, gives that a possible outcome for Calvin, is to not to succeed but to retreat or worse. If you like Calvin, you don't want that, or for his author.
It is a sad backdrop that colors the work, especially near the end of the run. I'd feel better about it if Watterson went on to new pursuits rather than going silent for years. That is was a good time to try something new, rather than a depression induced rage to end it.