Hidden lines were removed though only on a per model basis.

EDIT: But you don't have to believe me! You can visit https://bbc.godbolt.org/ and see BBC Micro Elite running in an emulator. Do a Shift+F12 at the BBC Microcomputer 32K prompt to boot the disk.

Also check out https://www.bbcelite.com/ (previously on HN: https://news.ycombinator.com/item?id=34852219) for all the code you can eat.