If you read ToS there is small print on reserving the right to change blah blah blah, and reserving the right to change, PSN terms of service at will. In fact you have no right to PSN, Sony could remove service if they wanted to.
With the only real disadvantage being that you can't use PSN I don't see how Sony are liable. Besides independently you can still do everything as advertised. You can use linux, you can use PSN. Just not from the same HDD anymore, the console still supports other OS as stated only its most current version of firmware did not.
What about developers who drop support on online games even whilst they're being sold @ retail? (like Nascar 09)
I'm pretty sure if you looked into it further nothing they're doing is illegal. Plus not enough people care. I certainly don't.
