I'm in violent agreement with you for most of that, and think that only good can come from this.
I believe all the LSB-certified distributions already have 5.8.8, so fortunately, I don't think
allowing 5.6 is going to even be a question.
But the LSB is not just a linux distribution standard. Its other side is a specification
for what API an application can rely upon. In terms of Perl, then, what does it mean to
have a LSB-compliant Perl application? What builtins/modules can be used or should be
avoided? Without a perl 5 specification (and I'm not suggesting creating one), how
meaningful is it to claim LSB-compliance for a perl app? And if that's not meaningful,
how meaningful is it to have a perl figure into LSB-compliance for a linux distribution
at all? The answers are not "completely meaningless", but they aren't all the way on
the other side, either.