We are not talking about perfection here. Of course there is always a potential attack vector. But when you look at virtually all of the recent major breaches, they were a result of gross negligence.
"Gross Negligence" is guaranteed.
Any solution that doesn't involve me securing my information w/ my own private keys (secured by whatever level of security I deem adequate) will lead to all of my private information released into the wild, eventually.
Fortunately, most of it is so out-of-date as to be worthless.
However, consider the implications. Even if I'm catastrophically bad at securing my data (for example, I print my private keys and give it to a few friends to put in their filing cabinets or whatever) -- some attacker can gain access to only the data they specifically target! Probably, a handful of low-value accounts, obtained at great expense using one-by-one attacks on individuals.
There is literally no approach vector that harvests all of the data for every account holder on some random poorly-secured rando's website, say, like AT&T!
I've been at this for 40 years. It's getting worse, not better. The solution isn't "more security". The solution is: the data simply isn't there, but in 8 billion individually secured hands.
Are there issues with this? For sure. But -- they only affect you, not your 1,000,000 neighbours.