No, I think GP is assuming that names are very complex, and even the assumption that people have a first and last name isn't always correct. You can just use a name field, and let people supply the name they want to use.

What do you really need a first and last name separated for anyways? Sorting? A salutation on correspondence? Sorting by last name isn't usually important[1], and you can generally use a full name in a salutation.

Depending on the domain needs, you choose the right representation. If you expect US citizens and want their name as entered on their tax returns or social security card, then you match what those can hold and note to the user that you are expecting those values. If you're just collecting a name to have a name, why put an extra constraint in there that doesn't matter?

1: Not to mention you then get to mostly ignore the craziness that is utf-8 and combining characters and cases and sorting.