They fully are computers. I wear hearing aids, and for example, one setting will glom onto voices in the stereo field and track them so the voice remains clear

They fully are computers. I wear hearing aids, and for example, one setting will glom onto voices in the stereo field and track them so the voice remains clear if they are moving around, while damping everything else. They do quite a lot, actually. They typically have 4 settings that the wearer can opt for. Some are "smarter" than others. The one I described is one of the more advanced functions.