In the digital gaming age, some Xbox console owners never have enough storage space. A new 4TB Seagate NVMe SSD is the largest Xbox storage card to date. Sadly, gamers may choose to delete titles rather than pay the high price of the expansion drive. https://www.notebookcheck.net/Seagate-launches-a-4TB-Xbox-storage-expansion-card-but-the-NVMe-SSD-has-a-surprisingly-high-price.1028827.0.html
Comparing the price of expansion storage in the PS5, a 2280 nvme drive, to the Xbox which uses a special drive around the size of a 2230 or 2242 nvme isn't really playing fair. The only 4tb 2230 or 2242 I could find was around $400 so the Xbox solution is fairly priced.
All that being said, Microsoft should have gone the Sony route and used a standard 2280 nvme over a customized drive.