Is this their peak strength or did they get even stronger after this point?
Important to note that they are already in their 30s by this point. If they are in their prime strength than we’d have to consider Xebec > Prime Whitebeard.
I'd argue the same for Garp and Sengoku. Did Roger's crew just decide not to intervene during their duels or is Bogard actually a Yonko level subordinate? I can't believe they actually kept the balance of power.
I've been thinking that too. But a lot of his actions still seem intentional, like wanting to destroy the world (maybe in a good way but idk), and Shanks having to capture him. Even in the worst case scenario I don't think he's evil.