"Blue Shield severed the connection between Google Analytics and Google Ads on its websites in January 2024."

They're lying.

Look at the page source for the announcement of the data breach. Use of both Google Tag Manager and Google Analytics.

     <!-- Google tag (gtag.js) -->
      <script type="text/javascript" src="/static/js/jquery.cookie.js"></script>
      <script async src="https://www.googletagmanager.com/gtag/js?id=G-KTK4E56VDB"></script>
      <script>

...

      <script>
  
        (function(i,s,o,g,r,a,m){i['GoogleAnalyticsObject']=r;i[r]=i[r]||function(){
            (i[r].q=i[r].q||[]).push(arguments)},i[r].l=1*new Date();a=s.createElement(o),
            m=s.getElementsByTagName(o)[0];a.async=1;a.src=g;m.parentNode.insertBefore(a,m)
        })(window,document,'script','//www.google-analytics.com/analytics.js','ga');

        var check_site_id = 347;

        var social_patterns = 
        ['facebook.com/share','twitter.com/share','linkedin.com/share',
        'pinterest.com/share','mailto:?subject'];

...