Where's your evidence it's a myth? Have you extensively studied Webster's dictionary?
[...]
The OED is only once source that gives a perspective from the British side not from an American side so can't be quoted as definitive.
Blimey.
The point I was trying to make is that a lot of people seem to think that -ize is an Americanism, and the only correct British English form is -ise, This is wrong: for some words it's -ize, for others it's -ise and for some both spellings are considered acceptable...
I've had a number of people over the years adamantly tell me that I've been wrong to spell a word with -ize. My usual response is to politely suggest they look it up in a dictionary. Most of those who actually bother to do so come back and apologize afterwards...
I did say however that some British sources are more relaxed about it. BTW, my extensive evidence in support is "Inspector Morse", who caught a blackmailer because they incorrectly spelt an -ize word...