This is bollocks. Speaking for Britain, and I think I can, there are hoards of would be victims to this kind of scam, particular of the current retirees generation, who are extremely vulnerable to having the wool pulled over their eyes about technical and internet security best practice matters, but for whom just so much as a poor turn of phrase or some unusually laid out punctuation is an absolute dead giveaway. If…
Educated, British retiree is one class of audience, who may need a different nuanced tactic (tech/ amazon/ gmail security like email with a professional English call center that can engage them).
The world is a big place. There are also other classes of audiences (where the engagement effort is much lower) and this purposeful spelling mistake does look like a good way to weed out some of them.