I think the issue is more with Moo*'s infatuation with Java-like error backtraces, which are rarely helpful. In most cases you want the bottom-level call within the code you're working with, not the full call stack in the maze of anonymous subroutine helpers that the Moo* family is so fond of.

Now that I talk about it, maybe a judicious application of Carp's %Carp::Internal could help clean up those tracebacks to a more manageable state?

#!perl
use strict;

package foo;
use Mouse;
use Mouse::Util::TypeConstraints;

# Converted to Mouse:
enum 'ErrorMode' => qw<carp error both>;
has 'error_mode' => ( is => 'rw', isa => 'ErrorMode', default => 'erro
+r' );

package main;
use strict;
use Carp;
$Carp::Internal{ 'Mouse::Util' } = 1;
$Carp::Verbose = 0;
my $foo = foo->new( error_mode => 'silent' );
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This eliminates at least Mouse::Util from the list of the backtrace. Most likely, more of these need to be added...