Yes, in that SBS he brought up WB, Shanks and Mihawk without a context. But in that other SBS, the fan specifically brought up Akainu's name to ask if X is stronger than Akainu, with Oda not only agreeing but going a step further to say X is even stronger than Kaido. That was when Kaido was already revealed. That doesn't make him strongest in history, but the strongest in the current story. Makes sense to refer to the strongest of the current story than reaching out to the past.