Elliot, I understand what you mean. However, if you have two or three names on your birth certificate, they are all your legal name. What has happened, not only with banks but airlines and other organisations, is that they now demand that you match your first name with everything.
Years ago, I dropped my middle name from documents with W being my first name and A my third. My credit card is AW and my bank WA. Some hospitals have me as W and others as A so anytime I’m asked my name now, I used a double forename! Much easier.