The way you are describing how the adsense network works recently (yes, some including me has been working with adsense since 2003 and we used to get human responses from Google adsense employees) makes it a high-risk business for publishers. Simply a competitor can inject a publisher adsense code in a dummy site that is against the TOS and report him, eliminating him from the network. Google is not stupid and it does understand this already and instead of banning domains (I am obviously speaking of adsense-banned domains, not Google index) like they used to be doing, they do ban the accounts itself. I am not a fan of the conspiracy theory but I see it intentional with "the new adsense".
They are either saturated with publishers and want to get rid of the majority of them, or they don't have enough employees to handle such mass bans in a manual way.
To those who will say "I don't understand what you are saying", refresh your thoughts with my original post about integrating adsense on a hosted network, and compare between what they were doing then by communicating with the publisher when something trigger a TOS violation and what they are doing currently by direct account-wide bans without prior notices. Ignoring the appeal requests seems to ensure that this is intentional.
This is at least the way I see things.