Headings allow for more structural, simpler navigation. Telling a user that something is a heading, is telling them that if they use heading navigation, they can easily return to this spot.
So the announcement:
heading level 4
Is very useful. It tells them that they are at a structurally important part of the page. It also tells them, that if they set the rotor to "headings" they can easily return to this spot by flicking up/down.
Now, this is all assuming that your tag is structurally important, and behaving as an actual heading, and not just pretty text. In this case you should use a different tag, and adjust with CSS to fit the styling you want. This is the most accessible solution.
You could also consider using the ARIA attribute role="presentation" on the element.
<h4 role="presentation" ng-if="voiceOver" class="keep-it-classy" ng-bind="getCurrentText()" aria-label="{{getCurrentText}}"></h4>
though I'm not sure if VoiceOver respects this for heading type elements or not!