Keep in mind that most x86 OSes don't use rings 1 and 2 at all (I'm not sure if they are even accessible in Long Mode, or if they were some of the legacy cruft which AMD decided to omit), and most modern CPU architectures only have user and supervisor (and maybe hypervisor) modes. This is largely due to the influence of Unix, since that has a binary user/root division; most later OSes agreed that multiple security levels weren't necessary, so both OS devs and hardware manufacturers started to ditch them by the early 1980s.
Multiple security modes were mainly a thing on older mainframes and minis, and even there it began fading by the time the 80286 came out. Most of the significant microprocessors have either had two-level security, or none at all.
The 80286 only introduced the current 4-level system used on the x86 because Intel were using it as a testbed for features meant for use in the still-unfinished
iAPX 432 (a completely unrelated microprocessor design which was proving too ambitious to be practical with the IC processes of the time), and even by then two-level hardware system instruction protection was the norm (for systems which had any; most microprocessors still didn't in 1982).
Whether this is a good thing or a bad one is left as an exercise for the reader.
However, it does mean that any OS which is meant to be ported to other architectures should avoid using rings 1 and 2, or at least not depend on them.