"My voice wasn't heard!" says the concerned citizen.
"We gave you a chance to give your comments at a public hearing" says the elected official.
"But I didn't know the hearing was happening!"
"It was posted on the telephone pole. Now please, move along."
The elected official had dozens of citizens at the hearing, so they can credibly claim that they notified the public of their plans. Why spend any more energy ensuring that everyone hears about it? People who support the plan don't care if they missed the hearing. So more visibility means more opposition. Unlikely, then, that the official will spend time and effort spreading their message.
Could the feedback process be improved by a grassroots effort? A simple app to list public hearings, which allows you to share hearings with people you think might also care. This platform could also have a way to aggregate feedback and deliver it to the elected official. If this platform became the fastest way for the official to know about opposition that was going to materialize anyways, then maybe it's worth paying attention to.