I’m not sure that’s a function of regulation but more a function of most modern freezers defaulting to -18°, where an American or industrial freezer is -22 to -28°C.

Getting a better energy efficiency score is one reason (and consumers are motivated on running cost, not just environmental) but presumably these are cheaper to manufacture as well.

I have an American style, EU-compliant freezer than I can set to -26° which I bought for preparing sashimi safely. It rocks! Highly recommend them.