If a "GNU program" means "a program that is covered under the GNU license",
then it may reasonable to call Linux a "GNU system". (Although even then,
a large amount of software that's part of Linux does not fall under the
GNU license; instead, it comes under the Berkeley license or Perl's
artistic license or similar, or it's not free software, e.g. Motif or
Netscape.)
This may be what you mean when you say "GNU program". However, I'm fairly
sure that this is not the way most people see it. To most people out there,
a "GNU program" is a program that is produced by the Free Software Foundation,
or a program originally produced by the FSF but possibly maintained by
someone else, e.g. GCC.
According to this commonly used terminology, Linux is not a GNU system;
far less than half of the software distributed as part of any of the
standard Linux distributions falls under the GNU license.
I think that insisting on calling Linux a "GNU system" is much more likely
to split the community than simply calling it Linux. Everyone around
knows what you mean when you say "the Linux operating system" and it's
not a politically-charged term, whereas "Linux-based GNU system" is.
ben
-- "... then the day came when the risk to remain tight in a bud was more painful than the risk it took to blossom." -- Anais Nin