I talked about this in another thread, but there are many reasons we do not use SD cards/flash memory devices for movies and TV:
SD cards have extrenely slow read rates compared to optical.
Optical discs are a much more reliable data storage format than flash memory devices. SD cards and other flash memory devices need to be used every few months, or the electric charge will wear out, causing the data to be unreadable. On the other hand, a professionally-pressed Blu-ray disc can theoretically last 50-100 years.
SD cards are more expensive to manufacture than optical discs.
I talked about this in another thread, but there are many reasons we do not use SD cards/flash memory devices for movies and TV:
I pulled an SD card out of the cupboard I literally haven’t touched in ten years and not a single file’s checksum had changed