Usually this is someone taking detours due to insecurity and needing to cover every base so no one can contradict any small detail. For people new to a subject it is much better to over simplify, even if there are technically caveats to what a presenter is saying.
To be fair, this isn't beginner content. This is the closest we have to master classes in game programming. I very much have met and can imagine the kinds of people in the field who would scrutinize every sentence and claim Casey makes. Hell Casey himself is the kind of person that would scrutinize every sentence and claim made.
I don't know what that says about the field and that subset of developers, but I get the angle Casey is going for.
Imho, I felt he was just passionate about the subject and went on potential “tangents” for the extra context. For example, he would sometimes go into some extraneous historical anecdote, but personally I enjoyed these.
But yes, perhaps the format is not for everyone thats for sure.
I can see some comments saying hes long winded, but he also provides written transcripts with diagrams too if you prefer to speed read through.
Hope he continues rolling out high quality videos going deeper into the subject matter. Overall an excellent course imho.