Since spelling was something most folks didn't take seriously until the 19th century, confusion is rampant!
You’re right about people’s varied spellings. There weren’t many “standards” until the advent of the dictionary. The first English dictionary wasn’t produced until the eighteenth century.
Standard spellings for names came even later, into the twentieth century & Scandinavians change their names at the drop of a hat. Even with all of the spelling changes, I've yet to come across any "Bridgett" among all of my Scandinavians.