local doesn't create variables. It just backs up the value of the variable and restores it later.

I know ^*. Certainly there's an internal difference; but it seems to me that the casual user is not likely to encounter much difference between

our $x;
CODE INVOLVING OUTER $x
{
    local $x;
    CODE INVOLVING INNER $x
}
[download]

my $x;
CODE INVOLVING OUTER $x
{
    my $x;
    CODE INVOLVING INNER $x
}
[download]

our $x; my $y;
sub twiddle { $x = $y = 'twiddled' }
{
    local $x = 'local?';
    my $y = 'local!';
    twiddle;
    say $x, ', ', $y;
}
[download]

^* Ah, but re-reading shows that I didn't seem to understand: I said something about having two variables with the same name, when really the localised $x is the same variable as the original one, just with a ‘temporary’ value. Is that misstatement on my part what you were correcting?

just that one's not likely to see it in casual use.

If a child scope has a variable with the same name as its parent scope, it would look like

my $x;
sub foo { ... $x ... }

sub bar { ... my $x ... }
[download]

What you said boils down to saying bar is unlikely to call foo, and I don't see how that is true.

I it is unlikely that the same var name is used at two levels in a working program, but that's something else.