The NPM monoculture is the problem. It would be absurd to suggest that all backend engineers use the same build tooling and dependency library, but here we are with frontend. It's just too big of an attack surface.

It would be absurd to make such a suggestion. However, the comparison is not correct. Not all front-end development uses the same build tooling or dependency libraries, or programming language for that matter. Even if you narrow to the typescript ecosystem, it's still not true.