OK, but what the parent is suggesting is that someone might store someone's personally identifiable information on "the blockchain", thus making the entire bitcoin network in violation of GDPR. It's a fairly on-point criticism, IMO.
let's say I'm a shop and i allow btc payments, but I include the customers info in the transaction or something to such an effect. then I'm in violation, and must pay a fine (since I can never delete that info). The network has nothing to do with this, and nobody else on the network is party to the violation.
Now we have a way to estimate the cost and we can just put that on top of the cost of using the service.
Boom, privacy bought.
You don't realise how absurd GDPR is?