why aren't gnu utils normalized?

[Bob Fry]

As a former user of Solaris and sometimes user of Linux or cygwin, I'm
puzzled by the continued lack of consistency in the options and
features of commands.  As an example, "join" does not understand a
numeric field sort.  Surely it would not be difficult to add this as
an option, but it remains much the way it was decades ago.  

I understand the desire for continuity but couldn't a new set of
commands be employed with a flag to use a modern, normalized set of
options? Gnu commands already have the long version but they seem to
mostly do the same thing as the old short version.
-- 
It does me no injury for my neighbor to say there are twenty gods, or
no God. It neither picks my pocket nor breaks my leg. ~ Thomas Jefferson