I came across CPAN Deep::Hash::Utils giving the approach below which seems simple enough. I also looked at the modules suggested by Re: A more elegant way to filter a nested hash? ( data xpath, dpath, diver, walk, walker, visitor, jquery, pquery, json path, css csel, MarpaX::xPathLike) and like the suggestions on existing art.

use Deep::Hash::Utils qw(reach nest deepvalue);

sub hash_filter {
    my ($source, $filter) = @_;
    my %rc;

    while (my @l = reach($filter)) {
        pop @l;
        if (defined( my $source_val = deepvalue($source, @l) ) ) {
            # hint: work around nest behavior on even vs odd key count
            nest(\%rc, @l)->{ $l[$#l] } = $source_val;
        }
    }

    \%rc;
}
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