Question about Google Pixel 8

I have a question about the Google Pixel 8 Obsidian with 256GB: According to the information available here, the storage space cannot be expanded. This is in contrast to the Google Pixel 8 in the Hazel colour. There, the storage space of 256GB can be expanded by a further 256GB. Is it really the case that the ability to expand the memory depends on the colour of the mobile? Or is it rather the case that some of the information is wrong or that I am misinterpreting it?