use strict;
use warnings;
use Data::Dumper;

my $path = '/.snapshots123/yabsm/root/hourly/day=2021_03_04,time=21:20';

my $end_of_path;
$end_of_path = $1 if $path =~ m/([^\/]+$)/;

my @nums = $end_of_path =~ m/([0-9]{2,4})/g;
print Dumper( \@nums );