The bios write protection for a Samsung XE500C21 can be removed?

For technical information https://www.chromium.org/chromium-os

From MRChromebox.tech

ChromeOS Device Firmware

The firmware used by ChromeOS devices is built around serveral open-source projects, and consists (mainly) of a hardware init component (coreboot) and one or more payloads (depthcharge for Verified Boot and ChromeOS, SeaBIOS for Legacy Boot Mode) which are subsequently executed. The firmware resides on an SPI flash chip… The shaded sections at the bottom are read-only, which is enforced by the firmware write-protect screw on the main board

Actually on this model, I believe there’s a switch under a panel on the side to get into Developer Mode. This will also erase the SSD. Also Chrome OS partition layout is crazy, with about a dozen partitions. It only gets more complicated from there. Have you looked into Crouton?