Although from out point of view the average people of the distant past were as stupid as rubber boots, the nobles were a bit better off, receiving education, travelling, meeting different sorts of artists, scholars, clergy, and so forth. Furthermore, the nobles had to always play their own little power games, which means they couldn't be entirely gullible, unlike many of the common men. That's why this chapter felt naive. The author probably tried to have the MC appear super smart and cook up some Gormenghast plans, but this is falling short and remains unconvincing. She's progressing far too fast and making too big claims to be believable, no matter how greedy the baron is.