I think I've mentioned this before (somewhere in 2018) but can't find the original post. I however, apologize if this comes across the wrong way.
One thing I've noticed when listening to speeches is that some speakers (not just politicians) tend to shout into the microphone and blast the sound system to emphasize their points. Raising your voice in a controlled pitch occasionally for emphasis is perfectly fine, but constantly shouting is neither necessary nor effective.
Personally, I find it distracting and, at times, quite uncomfortable to listen to.
On the other hand, those who have been trained in public speaking (speechcraft and toastmasters) often demonstrate a very different approach. They know how to use voice modulation, pacing, pauses, and emphasis to engage an audience without overwhelming them. In my opinion, that makes for a far more impactful and enjoyable speech or lecture.