Many people do. Personally I find "doomed resistance" works too depressing for me to get horny about them, most of the time.
Other kind of porn stories/games in the ToT style with femdom ladies conquering a kingdom that I'd be interested in would be:
-The realm already got conquered, and the MC, being the former king/prince, is given to the queen/empress and her court to play with
-The realm knows it can't fight off an invasion, so the prince MC is married off to the queen/empress so that the realm gets added to her land without bloodshed. Queen is very happy to be married to her brand new subby hubby puppy she and her court can train as they like.
-MC is among the highest-ranking knights/paladin of the realm, and his vows to serve the realm loyally are unbreakable. But before he can do anything to stop the invasion the king surrenders and all of MC's oaths and vows of obedience are transferred to the queen of the invaders, which he now must serve the best he can despite them being conquerors in a conquered land. Not helped by the fact he is a sub and attracted by the new mistresses of the realm. Could have fun scenes like the queen ordering MC to go enforce her rule, promising degrading rewards if he does so, then saying he did it due to being horny for the reward rather than him being just that loyal to his duties, or the queen ordering the MC to participate in a chivalry tournament where the one coming in last place is incredibly severely punished and to lose every events on purpose, which he does for the first day, then for the second day she puts her stockings around his head, seals his helmet on, and order him to win the tournament in her name, which he does.
-MC is a page dreaming of becoming a knight, and the day him and his fellow squires-in-training are each assigned to a knight to serve is finally here. Except the realm gets blitzkrieg'd during the ceremony and the femdom ladies' general personally curbstomp the assembled knights and higher-ups. MC has enough guts to attack her despite how outclassed he is, and once defeated he offers him his life to do as she pleases since it's the honorable thing to do (as opposed to the higher-ups who all bitched or begged to be spared in terror when she beat them). The general is impressed enough she declares he will be her squire from now on while the rest of the squires-in-training are given to her subordinates. Of course, the curriculum of knight training changes significantly under the new overlords...
-MC is a young mayor or very minor noble (like, a baronet) whose town is suffering from a plague/monster infestation/curse/etc. Out of option, he travels to the capital to petition the king for help... only to find out that while he was traveling the realm was conquered by femdom ladies. He nevertheless decides to go to the new queen's first court session, where most nobles go all how-dare-you before getting put in their place. When it's MC's turn, he begs for his town to be saved, to which the queen answer with a "sure, if you swear to be my pet forever" and to everyone's surprise he agrees to it as his town's citizens' lives are more important.