I run into this all the time as well. As I said in this or another thread, my Siamese are really nosey, so when people come over and site down, they converge on that person. People who know my cats, know that they only want attention and to be talked to and petted. But people who believe this stereotype freak out and think they are being attacked!
I have a 5 year old son and a 3 year old grandson (long story), and they play rough with the cats. Never harming the cats of course. They've been raised around cats all their life. And not once have the cats ever harmed the boys. They will bat at the boys, but they always retract their claws.
I'm just baffled by this reputation they have. Although, I blame Lady and the Tramp in part as well. I can't tell you how many times I've heard people use that movie to justify their misinformation about Siamese.
I do understand if you had a bad experience, especially as a child with a particular breed it might make you leery of them in the future. But an aggressive or stand-off-ish cat could happen in any breed, and shouldn't reflect them as a whole.
o.k., I'm sorry.
This is one of those subjects that 'take me there', if you know what I mean. I'll stop now.