First, yes: there absolutely should be better tools for authors to sign & authenticate their own tools, with heightened cryptographic authentication means. Projects like sigstore get this (and wish to respect privacy![1]). But what's spoken of here is a deep imposition, and doesn't empower authors, but demands of them.
> I fail to see how MFA resolves the fundamental trust equation
Nothing ever will. Your desire for a cathedral is incompatible fundamentally & at every level with the bazaar.
Trying to drive open-source society towards an industrialized security state for the convenience of your probably non-contributing, not-paying industrialized software production needs is vastly unfair.
If you have needs, you need to take your own responsibility. If you have risks, you need to pay to hedge them. Go hire NodeSource to help you get the Certified Modules you can trust. Go sign contracts with authors to get the support you need. Heck, just checkin your package-lock.json and go see what you are downloading: npm is immutable! You could literally do anything to help safeguard yourself, but you ask for absolute protection, something that even the biggest best corporations can never truly promise. Trying to prevent even one reasonably placed malicious employee from causing disruption is a near impossible task. But you ask for a fundamental safety. This is laughable. None of us can expect nor deserve that.
> Until GitHub requires government-issued photo ID in addition to MFA
What a vile & fascist imposition this would be! Woe be unto us if industrialzied software so hotly presses for it's own security that it embraces such ludicrous & perverse a cowardice as this. Relying on github as your source of trust, and pressuring them to pressure the world into turning over core information, is just as antithetical as I can image to the open source behavior & society that has advanced us so far. What a terrible thing to wish for! Egads, gross.
[1] https://blog.sigstore.dev/privacy-in-sigstore-57cac15af0d0 https://news.ycombinator.com/item?id=31533997