Even an async validation would be better. I have <common name>@gmail.com, and get several newspapers and some other subscriptions for free.

In one case, a person named Mary in Australia sends their loved one a gift card every year, and the retailer doesn’t provide any information about Mary. In another case, a student missed out on their work study job and a opportunity for early class enrollment due to a bad email.

It’s sad as all of these customers don’t even know that they have a problem.