I believe the engine is multi-platform but the editor is Windows-only at the moment.
https://o3de.org/docs/user-guide/platforms/linux/
(PS: not being coy, just confused by conflicting documentation)
> Implemented support for Windows, MacOS, Linux, Android, and iOS editor and runtime builds
Perhaps the documentation stating that Windows is required is merely out of date?
[0] https://o3de.org/docs/release-notes/archive/2107-1-release-n...