The 'sh' pronunciation is pretty well-known, in the UK at least, due to exposure to it in Catalan (particularly with CaixaBank) and Portuguese. I suspect that most people here would guess that Spanish still pronounces it that way too, thanks to México and Xérès / Sherry.
And there's Xitter, of course, which is a fairly common way of referring to the social network formerly known as Twitter.
>I suspect that most people here would guess that Spanish still pronounces it that way too, thanks to México and Xérès / Sherry.
Sorry, what? First, is the word "Xérès" well-known among English-speakers? Second, "México" isn't pronounced "méshico", so how is it a supporting argument at all?