Your argument is "People new to Perl should not use Moose and should create their own object systems because that way they can look in CPAN modules and understand what's happening"? That's silly. If you look in my Mail::TempAddress, your knowledge of blessed hashes won't help much if you don't know anything about SMTP and mail server configuration.

Assuming that a primary goal of people trying to learn OO Perl really is to understand CPAN modules, what about wanting to understand the 15% of the code on the CPAN that uses Moose?

(I'm tempted to argue that Moose makes the OO concepts easier to understand by not exposing the Perl 5 mechanism of OO; someone who understands OO can understand Perl 5's mechanism much easier. The other way around is more difficult.)

Your argument is "People new to Perl should not use Moose and should create their own object systems because that way they can look in CPAN modules and understand what's happening"?

No, it is not. And I think you know that.

Assuming that a primary goal of people trying to learn OO Perl really is to understand CPAN modules, what about wanting to understand the 15% of the code on the CPAN that uses Moose?

Since Moose itself is based upon those pesky blessed hashes you seem to abhor, I don't see your point here.