Yes....because thats literally what is explained in the story and by Blackbeard himself lmao:
If Teach was literally born with the ability to eat multiple fruits, why not start with a different one and eat the Yami when he finds it?
The original reason in story that the Yami was special is that it could damage Logias, but obviously Haki made that not a big deal, most likely Teach wanted the Yami as a way to get more devil fruits.
Btw, how does Ace, Oden, Wb, the Marines, Kuzan, or any other BBP not notice Teach is multiple people, but Luffy and Zoro can? Why does Teach talk about himself like he is one individual? "This is *my* era"