I have nothing against Americans! (well, apart from Trump). But most of the Americans I know have names which are totally acceptable and normal here too - Tom, John, Michael, Elizabeth, Caitlin, Lara, Susie.
The American names I object to are the "made-up" ones - Brayson, Cashley, Everley, Landon, Paxley, Addison, Emerson, Camryn... Just awful.
As for the "surnames as first names" thing, yes it's very common in some parts of Scotland and NE England. Like the actor Robson Green. My kids (Scottish) have surnames as a middle name. BUT - and it's a massive but - McKenzie, McKenna and butcherings like Makenzy or Makynna do not fall into that category. McKenzie means "son of Kenneth".
And don't get me started on people who name their children after British places they've never been - Paisley, Camden, London, Harlow, Bristol - looking at you, Sarah Palin. Even more awful.