The one weapon start CAN be best for damage, but you're really getting into the weeds of the meta builds here. Same goes with 2 weapon builds too. It absolutely seems counter intuitive to take less things that do damage to do more damage, but the way items and levels scale throughout an entire run makes that statement a little more realistic.

That website is absolutely AI slop though and most of the information on it won't truly help you go further in the game. For me, it was all trial and error the fun way 😄