jQuery .sort() function working in Safari and Firefox but not in Chrome

Question

I'm running this script and it re-sorts my divs correctly (by date ASC) in Safari and Firefox, but not in Chrome (mac). Any ideas why?

$('.item').each(function() {
  var ts_date = $(this).attr('data-date');
  var t = ts_date.split('-');
  $(this).attr('data-_ts', new Date(t[0], t[1]-1, t[2]).getTime());
}).sort(function (a, b) {
  return $(a).attr('data-_ts') > $(b).attr('data-_ts');
}).appendTo('#items');

<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<div id="items">
  <div class="item" data-date="2020-01-02">Should appear last</div>
  <div class="item" data-date="2020-01-01">Should appear first</div>
</div>