Is <sp-tooltip> restricted to buttons only?

I’m wondering about the behavior of tooltips, because I’m looking at the UI Kitchen Sink that Adobe provides.

I wish to have an <sp-label> element show a tooltip whenever the mouse hovers over.

The UI Kitchen Sink example has a button with a tooltip example like so:

<sp-button class="tooltip">Hover over me
          <sp-tooltip open placement="top" variant="info">I'm a tooltip!</sp-tooltip>

I can get this method to work on <sp-action-button> elements, but I cannot get this method to work on <sp-label> elements, with identical code except for changing sp-button to sp-label.

Since there’s always new CSS to learn, maybe I’m forgetting some fundamental rule about this. If anyone has any pointers, it would be greatly appreciated!

The answer is that there is insufficient support for the built-in tooltips. I should, instead, focus on the <div> over which I wish to have info hovering, and paste the info in a <...title='stuff'> attribute.