Honestly I think it's kind of worrying that this opinion is so popular. Aren't you essentially saying that frameworks are in most cases useless, and "job security" is something you should strive after?

First of all, "job security" means that you're irreplaceable, and in the case of you actually being the architect/designer, that probably means you did a (perhaps intentionally) bad job to make yourself the linchpin. Not good.

Secondly, regardless of the first point, programming is hard. Anyone that says otherwise should be avoided like the plague. It's beyond the scope of one individual to be able to keep up to date to all the security issues and gotchas prevalent in a language or ecosystem. This is why you use frameworks. They're democratic units that within themselves handle patches and development in ways that are often better than one "irreplaceable" developer on a unique object (of course, bad developers can still use frameworks and derail the product completely to the point where all benefits of the framework are negated, but that's beside the point).