> new Morphos [...] will not be compatible with actual softwares whitout
> recompilating all programs. [...] it will be binary uncompatible.

There's also endian-dependency on source code level in software that is not written in an endian-agnostic way. See WebKit's JavaScriptCore for instance. This may be the case for the source code of certain AmigaOS/MorphOS legacy software as well.