They can and they already do, LNG from the US is flowing in. But swapping dependence on Russia for dependence on the US isn’t the clearcut win people imagine. Washington is in the middle of its own trade war, and Europe is one of the targets. Pax Americana is over, and Europe is treated less as an ally than as a vassal. The US openly exploits Europe’s fear of Russia, turning a legitimate threat into a lever for domination. What Europe gets is dependency and vulnerability, while the US extracts obedience and profit.
The irony is that the US slaps higher tariffs on most European countries than it does on Russia itself. As the old saying goes, "it may be dangerous to be America’s enemy, but to be America’s friend is fatal".
Are you sure that is accurate? My research found that since the invasion, Russia’s MFN was revoked and Column 2 rates + import bans make US barriers on Russian goods much higher overall than on EU goods.