Just for fun, here's a case where a loop is still needed for s///g

#!/usr/bin/perl

use strict; # https://perlmonks.org/?node_id=11159009
use warnings;
use v5.36;

#my $x = "xyzzy foo1 foo2";
my $x = "xxxxxyyyyyyyyxxxyyy";
my @captured;
while ($x =~ s{ (xy) }{}msxg) {
    push @captured, $1;
    say "To Go '$x'";
}
say "Captured: '$_'" for @captured;
say "Left with '$x'";
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Outputs:

To Go 'xxxxyyyyyyyxxyy'
To Go 'xxxyyyyyyxy'
To Go 'xxyyyyy'
To Go 'xyyyy'
To Go 'yyy'
Captured: 'xy'
Captured: 'xy'
Captured: 'xy'
Captured: 'xy'
Captured: 'xy'
Left with 'yyy'
[download]