Password breaches (generally speaking) don't occur because users choose poor passwords, they occur because the security of the site is poor.
If your question was instead "Will 1Password (or similar tools) rescue us from the ramifications
of password breaches?" then the answer could instead be somewhere between "Maybe" and "Yes".
The ramifications of a password breach can be huge because people who aren't particularly IT literate (and unfortunately, some people that are) tend to use the same username and password for every site they sign up for on the Internet.
As a result, when their details are compromised on one site (say, LinkedIn), then the attacker could now theoretically log in to the person's eBay account if the details are the same. As an attacker this is a great strategy, because if you want to go after someone's account on a site with good security you just need to compromise their details on a site with lesser security.
If, however, people used strong, unique passwords for each site they signed up for then it is likely the ramifications of any breach would be less than they are now.