It is however realistic for Google to solve this by putting a violating account in a "read-only" mode, where you are able to export all you data and not do anything else.
Allowed access to banned accounts in "Read-only" mode is ripe for abuse by spammers and phishers who could benefit from still being able to access information in the violating accounts. Its the wrong kind of solution to a problem that really comes down to personal responsibility.
I think most people know deep down the responsible thing to do is have backups of all their important data... the cloud is just making people lazy. And providing a "read-only" access to a banned account will only make people lazier and more apathetic about it. "oh.. no worries.. Googles got my back" But what happens when Google is hacked, or suffers a natural disaster, or other catastrophic failure? It only serves to make the problem worse. Losing your data, to even a wrongfully banned account, is nobody's fault but your own.
There so many more reasons to backup your data before something bad happens, not after.... thats what we should be promoting
Regarding spammers and phishers, these are users violating the law and they of course have no legitimate claims to their account data.
This philosophy, or at least the "out" part, should apply doubly after someone's account is terminated in this manner. Google has determined that sinning against one service warrants terminating access to other services. That may be justifiable. But sinning against one service should not warrant loss of one's data in other services.
4.4 You acknowledge and agree that if Google disables access to your account, you may be prevented from accessing the Services, your account details or any files or other content which is contained in your account.
I have no knowledge of what services he can or can't access, just that it is within Google's purview to remove access to all Google's services.
P.S. This is not Twitter and we don't use hashtags in our posts. Please act as though you have a semblance of decorum.