That's not what they meant. Yes, anybody can write bare metal alternative to Linux ( at the very least by looking at the Linux codebase). But still that Pi 1541 depends on the bootcode.bin, fixup.dat and start.elf binary blobs, which the OP was complaining about.
It wasn’t clear to me what they meant. I’m not familiar with the details of boot.bin but my read of what GP was implying was you had to use the rapsbian kernel and drivers. Thanks for the information.