So it's possible to actually wordmark / trademark a common first name?
One of the largest retailers in Canada is "RONA".
It is also a female first name.
ANYTHING that serves as a distinctive identifier of the source or origin of goods can function as a trademark.
Your question concerns the scope of a mark, about which there are more crazy ideas among domainers that I've long given up hope of trying to broaden the general understanding.
Let's say I make a brand of dog food named "BULLHORN". I like that name because I have a picture of a big mean bulldog on the can. It's something of a regional brand, but in order to protect expansion of my market in the US, I register my mark with the USPTO.
Okay, fine, what does that mean?
Can you use "BULLHORN" to sell bullhorns? Well, yes, of course you can, because that's what bullhorns are called. My brand is for dog food.
Can you use "BULLHORN" to sell cat food? Unlikely. Even though my mark is for dog food, it might be reasonably anticipated that I would expand into cat food, and consumers might expect that "BULLHORN" brand cat food comes from the same people who make "BULLHORN" brand dog food, because it is a distinctive name for pet food or pet products in general.
Can I used "BULLHORN" to sell jewelry? Probably. There is no reason to expect that "BULLHORN" brand jewelry comes from the same people who make "BULLHORN" brand dog food.
Is that true for all marks? No. Some marks are "famous" - i.e. they are so strongly and exclusively associated with one party that any use is likely to dilute the value of the famous mark. For example, if you saw a pair of shoes that said "COCA-COLA" on the label, you might expect they have something to do with the Coca-Cola Company, even though they don't make shoes.
I've researched the tess database and found 4 wordmarks for the name
Owned by the same party, or by four different parties? The number of concurrent users of the same term as a mark is a significant consideration in the scope of a mark. Conversely, the extent to which a single owner has developed a "family" of marks is an indicator of increased strength and scope.
In the TESS database, the phrase "word mark" is merely an indexing term. Do you mean a mark with "standard characters" claimed?