I'm having difficulty deciding whether to build a new ruby gem in ruby 3.0.1 vs ruby 2.7. Is ruby code written in versions >=3.0.0 backwards compatible with versions >=2.5 or >=2.7? Can somebody working in ruby 2.7 consume a gem written in >=3.0.1, on the same note can someone working in >=3.0.1 consume a gem written in ruby 2.7? Are there any breaking changes in 3.0.1 that make it difficult to upgrade from 2.7?