Its not a matter of how often people write it: The syntax allows it, so its not a syntax error. This has a deeper meaning than you think - because it is not possible to detect this problem unless in the scope of an execution. Consider this:

my $name = 'est';
*{$name} = sub { print "hello\n"; };
est();
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Even if strict is on, who is to say the assignment of the glob doesn't happen under the scope of no strict 'refs';? You could argue that anything you don't personally use... should be a syntax error?