Because the article's title specifically states that every CS major should know those topics. Should every CS major know formal methods, AI, robotics... ? Yes

Because the article's title specifically states that every CS major should know those topics. Should every CS major know formal methods, AI, robotics... ? Yes the heavy math you took was very helpful (and I personally agree as someone who did a CS heavy math degree), however as stated above the list should really be a minimum requirement. Anything extra is superfluous.