You are moving the goal posts. Of course simple data storage can be made secure, because you have the key. But the article is talking about financial data that is processed by companies. And you mentioned healthcare data, which would also be processed. The companies have the key and they can be forced to hand it over easily.

What use is end to end encryption for your healthcare data, if nobody except you can process that data? In that case, why don't you just put it on some external hard drive?