I used to think that about Napoleon as well. That is, until I started to read more about him. This is part of the reason why I don't like "typing" people anymore until I know enough about them.
Let's start with Napoleon at his
worst. His temper. I think I'm only being honest when I say that ISTPs have some of the worst tempers. It's a combination of a reactionary Te function, with a repressed Se. And Napoeleon's temper was apparently not "learned"; he had it all his life. When he was a kid, he was hot-tempered, and would often wrestle or fight his older brother. When he got the equivilant of what we would call a "girlfriend" now, his schoolmates would tease him about it, and he would chase them down and fight them!
Sounds like the kind of teasing types with a poor Fe aren't good at taking. I don't know many ESTPs who are like this. This kind of behaviour continued throughout his life. When he was older, it wsa said that his fists often got in the way (striking people of both sexes). Again, ESTPs are rarely reactionary or overly aggressive. Napoleon was very "defensive", which is more Introverted.
There were other things, such as he was known to feel great and strong one day, then slip into depression the next. He was also somewhat more paranoid, which is an Ne dual-seeking funciton. Also, he was said to have more routines or superstitions. Falling into routines is more of an Introverted trait, again. When young, Napoleon would also follow his father to taverns, because he had a gambling addiction. Then Napoleon would watch and record what his father did.
One other thing is that he had a love of history and would often read books about past leaders. I know this one is just a stereotype, but ISTPs are more interested in reading about that kind of stuff, whereas ESTPs have little patience for it.