When a regular guy is mysteriously transported to an exotic setting, we want the guy to be authentic and the setting to be imaginative. For authenticity, the author can either create a character of his own nationality and social milieu or alternatively can give the character some different background. In the latter case, we might recognize the background.
I am not the same kind of guy as Malcolm Lockridge in Poul Anderson's The Corridors Of Time or as Duncan Reid in his The Dancer From Atlantis. James Blish, an American living in England, created John Martels for A Midsummer Century. Martels is a University graduate, a radio astronomer and a British emigre to the US. I can identify with the graduate and the Brit but not with the radio astronomer or the emigre. (Incidentally, Blish's purpose was to revive the old narrative technique of starting in the here and now before whisking his character to somewhere/when else, in this case a far future. However, Martels had already been transposed to an exotic setting, the US.)
I have some things in common with Patrick O'Rourke in SM Stirling's Nantucket Trilogy. Like O'Rourke, I once studied Law in Dublin and also worked in the US one summer - although I was not on Nantucket when it time traveled. My escape from the mundane was to transfer from Law to Philosophy and Religious Studies - and I was already reading sf, which is how most of us time travel.