Sam4231: There doesn’t seem to be a nafka mina in a plain reading of the halacha. The prime example the SA gives for mitztaer is the inability to sleep due to bugs odor or wind, but only if not expected, and one cannot build a sukkah in such unpleasant circumstances and claim to be mitztaer, or iow you were mavatel the mitzva. The Rama’s calculus says if it is unusable for any basic function that you home provides, it is not a sukkah.
One nafkamina is that unlike most halacha, mitztaer is somewhat subjective. Thats how in places like Petrograd, they bundled up, put on the fur hats, and drank hot, fermented borcsht in conditions that the SA would say is patur. With the same subjectivity you might say that the stymied lone sleeper is not yotzee eating breakfast either, but his guests who had no intention to sleep there, are yotze eating there. I know one fellow, locked and loaded, who would love nothing more than an intruder. But the halacha generally doesn’t focus on the odd case. Run this by your LOR.