As we know there are a lot of connections between Blackbeard and the Rocks Pirates.
There is this old theory about Blackbeard being a fake D. given that he didn’t smile when he was about to die, unlike all the other Ds we’ve seen, and that Whitebeard said that he wasn’t the one Roger was looking for.
Anyway I think that Wano arc chapters solidified it.
1– The Rocks Pirates had their home base at Beehive Island, the same island Blackbeard is at now.
2– Rocks’ full name, Rocks D. Xebec has two things relating to Blackbeard: the D. obviously and, as revealed in the Vivre Card data set, Blackbeard’s ship is called Saber of Xebec.
These two additional points, while seeming small, are insanely valuable for us to determine Blackbeard’s part in the story. He is trying to fit himself into the idea of the ruler of the world, just like Rocks D. Xebec. While he is admiring Rocks, he is just trying to will this idea of him being a chosen one into existence, even though fate and inheriting will aren’t going to work that way.
Blackbeard understands the nature and importance of the inherited will, that’s why he gave himself the D. name, by trying to just absorb the will of Rocks D. Xebec, whether he was intended for it or not. He is trying to take everything Rocks D. Xebec did (his headquarters, naming his ship after him, and I’m sure other things that we don’t know yet), and adjust his view of history to match him, like he was the only one to see it.
Upon learning of Rocks D. Xebec and his crew we can clearly see the similarities between what Rocks and his crew had and that which Blackbeard is trying to emulate. This band of powerful thugs who banded together and almost conquered the world.