[Isofarro]

1.) Screenreaders have different modes of operation for different aspects of web content. For dealing with Forms they have Forms mode, in which only form elements are announced. A link isn't a form element, so they wont see the submit button.

2.) Screenreader users have a shortcut key to submit the form - typically when under-qualified web developers create forms without submit buttons. This fires the form submit event, which without a JavaScript preventDefault will get the form contents sent to the URL mentioned in the action attribute on the form. So the screen reader user's comment is treated as spam.