The cross-realm argument for packages like is-string is the one I find hardest to dismiss, but even there the math doesn't add up. The number of projects actually passing values across realms is tiny, and those projects should be the ones pulling in cross-realm-safe utilities, not every downstream consumer of every package that ever considered it. The deeper problem with Pillar 2 is that atomic packages made sense as a philosophical argument but broke down the moment npm made it trivially easy to publish. The incentive was "publish everything, let consumers pick what they need" but the reality is consumers never audit their trees,they just install and forget. So the cost that was supposed to be opt-in became opt-out by default. The ponyfill problem feels most tractable to me. A simple automated check "does every LTS version of Node support this natively?" could catch most of these. The e18e CLI is a good start but it still requires someone to run it intentionally. I wonder if something like a Renovate-style bot that opens PRs to remove outdated ponyfills would move the needle faster than waiting for maintainers to notice.