The better question is the seek latency. The bandwidth for read isn’t too horrible, if the seeks can be kept within reason. This is somewhere between tapes and actual pressed optical media (not dyed /re/writeable). Should seek way faster than tape (maybe even on par with BluRay) and 30Mbps read is manageable for doomsday scenarios.

Long term databanks. Libraries. GitHub’s archive bunkers. Microfilm replacements.

at theoretical perspective, if the X-Y plane can be addressed with 16-bit DAC by controlling laser deflection. then to seek any data with in a 4GB address space will have typical latency of 300us with the latest laser scanning technology.

I am not aware any laser scanning technology that can do 16-bit accuracy that has no moving part. so, fundamentally, this is a storage technology with mechanical addressing.

laser can be scanned by acoustic wave, but that itself lack the beam pointing accuracy. the ultrasonic drive frequency will limit how fast is can deflects the laser beam.