The fact that PayPal claims to be the safest payment solution is pretty irrelevant, especially if it's meant to be safest for the buyers and you're the seller. This is not the first story of PayPal freezing accounts with substantial amounts of money and not talking to the account owner.

Also, their ToS are pretty clear that they can do whatever they want, based on their beliefs, and there are no explicit limits how long they can keep your funds, or even obligations to talk to you. It might work differently in the EU, where they are registered as a bank (and so are regulated as a bank), but in US that's not the case IIRC.

The behavior is not all that unexpected - it's easier and cheaper to loose a customer receiving a lot of complaints than to inspect each of the complaints. So while I understand this is pretty damaging and dislike what PayPal does, I'm surprised that people are surprised.