What platform isn't personal? Sure, you don't use your real-name here or there, but it can and will be linked to you in the future. Any online and offline activity has a real chance of being linked to you at some point in the future.
true enough, but as long as law enforcement don't need to get involved (obv don't do stupid stuff) a username is easier to throw away then a Facebook account... But even then I suppose it wouldn't be possible - Big Brother here we come.