Content tracking: Why isn't Matomo finding my content pieces within the content block?

Consider the following HTML markup:

<ul data-track-content data-content-name="Global Navigation">
   <li>
      <a href="/" data-content-piece="Start">
         <span>Start</span>
      </a>
   </li>
   <li>
      <span>Company</span>
      <ul>
         <li>
               <span>About Us</span>
            <a href="aboutus.html" data-content-piece="About Us">
            </a>
            <ul>
               <li>
                  <a href="team1.html" data-content-piece="Team 1">
                     <span>Team 1</span>
                  </a>
               </li>
               <li>
                  <a href="team2.html" data-content-piece="Team 2">
                     <span>Team 2</span>
                  </a>
                  <ul>
                     <li>
                        <a href="team2-people.html" data-content-piece="People">
                           <span>People</span>
                        </a>
                     </li>
                     <li>
                        <a href="team2-tasks.html" data-content-piece="Tasks">
                           <span>Tasks</span>
                        </a>
                     </li>
                  </ul>
               </li>
            </ul>
         </li>
      </ul>
   </li>
</ul>

I can only see Global Navigation - Start in Matomos Behavior > Content area. I can never see any of the other content pieces like About Us or Team 1, but they are all contained within the content block.
When I do manual tracking in the browser console it shows up in Matomo:

_paq.push(['trackContentImpression', 'Global Navigation', 'Team 1', 'team1.html']);
_paq.push(['trackContentInteraction', 'click', 'Global Navigation', 'Team 1', 'team1.html']);

The navigation is not added dynamically. Am I doing something wrong? Is the hierarchy depth too deep for Matomo to find the content pieces?