> What do you really need a first and last name separated for anyways? Sorting?... Sorting by last name isn't usually important...

When paying customers / clients want to sort by last name, because “that’s how we do things”, then you sort by last name. So it’s only important when you want to make money.

Edit to add: your customers also don’t care that someone somewhere has 6 first names and no last name. “This wasn’t a problem with our old software.”