They are not required to do real support.
But since they openly state that the email address is not monitored, they do not fulfil the requirements of the law.
It's perfectly fine never to respond to any email sent there.
They just have to accept that mails sent there can have legal effects.
The problem is basically that by telling everyone "I don't read it" they are suggesting to others that they cannot successfully (in a legal sense) contact Google using that email address. And that's wrong.