<< Solved >> Big Sur unable to boot

[PrasadK]

The only other thing that I can think of that might help is flashing the firmware.

I assume you are referring to the SSD (Samsung 980 M2 NVMe). I am not seeing mac based option for but will look around. BTW, I tried in windows with diskpart as well. No such luck

 

[PrasadK]

Thanks, @P1LGRIM @Feartech @pastrychef for trying to help me.

 

[PrasadK]

Look at this article. Seems like an known issue of Samsung drive going into read-only mode... I can't believe they didn't email people about this proactively when this firmware was released. I bought directly from Samsung.