A failure to update software is only a small part of the issue. There is truly no such thing as a secure computer system and it's unreasonable to expect something impossible from every company.
The real problem, is that companies are allowed to amass and profit off of private information in the first place.
Even the Equifax breach is just the tip of the iceberg. We Americans desperately need a constitutionally guaranteed right to privacy. It's not even an individual rights issue, data breaches of this size are an extreme risk to national security.
Something like 2 factor authorization on credit approvals would be nice ... but identity theft of an individual is actually not that severe of a consequence when you consider what ISIS and North Korea will almost certainly doing with this data. If you've ever had your fingerprints taken or applied for a government job, all information provided in that process was already stolen years ago. The only way to avoid these hacks, is to limit what these databases are allowed to indefinitely store in the first place.