Also, something passing state-wide in a populous state like New York or California can be regarded as an end-run around the difficulty of passing such a law nat

Also, something passing state-wide in a populous state like New York or California can be regarded as an end-run around the difficulty of passing such a law nationally. Vendors won't be willing to lose sales in large markets, so everyone else will get New York-compliant phones. Compare how Texas controls the market for primary/secondary school textbooks in the US.