

Tariffs only apply to physical goods, not services. And tariffs are usually based on origin, not seller. The physical goods those produce don’t come from the US, so they are mostly safe from tariffs. We need to have a digital service tax, but that should used to finance the digital commons (e.g. foss projects), not as a trade bargaining chip.
Different mains voltage.
EuropeMost of the world uses 240v and the US 120v.The formula for power dissipation is
P = V²/R
where V is voltage and R is resistance. So electrical kettles take more time to boil water in the US.