It's crazy to think that the Macbook SE will start with 64GB of SSD like you suggested. The $400 iPhone SE starts with 64GB. For $750, 64GB would get laughed at by every reviewer and every user. It would become a joke of the industry and the SE brand would take a huge hit.Offering a low storage base model on the SE device, like the base iPad, which is essentially an SE.
No one is buying a $750 laptop with 64GB of un-upgradable storage in 2022.