Background
I have a name that English L1 speakers find hard to pronounce.* One of the first questions I get whenever introducing myself to one, is ‘Can I call you […]?’ After years in the university sector I have come to know many people from many different countries, but on no occasion has that question come from English L2 (L3, L4 …) speakers. As an aside, I remember Jeremy Clarkson joking about his own experience in the US, how they insisted on Jim or something similar because his name had ‘too many syllables’ for the Americans.
Nicknames and abbreviated names are of course not unique to English; in my own native tongue I know many who were known exclusively by their nickname our initials. But the insistence on requesting a different name than the one provided, is something I myself have only experienced with English L1 speakers.
Question and subquestion
Why is there (seemingly, alleged, &c) a proclivity for English L1 speakers to request using an abbreviated name over the one given them? Which differences or similarities in this have been found between IE languages? Are there any meaningful differences in this between the major L1 English variants (British, American, Canadian, Australian, Indian?)? Or is this simply a cultural thing, not related to language at all?†‡
Notes
Remarks
* If relevant, I am a white European culturally and linguistically.
† Though it is worthwhile stressing (as mentioned) that at least in my experience, none of the many other nationalities I have met (e.g. Czech, Danish, Finnish, French, German, Italian, Korean, Russian, Slovak) have requested this.
‡ If I by accident insulted someone by asking this question the way I did, I apologise in advance and kindly ask for constructive criticism on how to rephrase the question.