It's not practical. I looked into it once on a related matter and unless you're a US state dept employee or member of the military, the fees and taxes on importing and registering a car bought outside the US are astronomically high, like the cost of the car all over again, tens of thousands of dollars. The US has very specific and nit-picky safety standards. It's not a matter of meet or exceed, it's a matter of meet and don't exceed the limits imposed by law or regulation so you can't buy and bring over a European car that has better safety features if they don't meet US standards, so in that case you have to pay a specialty mechanic to adapt your car to US standards. And even if the standards are met exactly there are huge taxes and fees on it to discourage people importing cheaper cars. This is not the first US rodeo with protectionism for US car companies, they did this whole thing with Japan in the 90s and the Japanese eventually just did bulk importing and then later set up US plants for making the cars to get even lower costs.
Those for whom it might be practical would represent a few hundred thousand, maybe a million or two people who live very close to the Mexico border and don't just not registering in the US and dealing with the Mexican paperwork regularly.
That's not happening. This is meaningless talk.
They're still withholding the machines and maintenance to the top end processes from China on national security grounds. They've already committed economic suicide. Germany is blaming Ukraine for the Nordstream attacks.
They lost their chance for independence this decade with the blowing up of Nordstream and when they all jumped onboard with anti-Russia sanctions and supplying weapons. The US has an interest in keeping the war in Ukraine burning or ending in a Korea type situation without a clear winner to keep Europe off Russian gas and reliant on US gas. Meanwhile the US poaches their talent, empties their industry into its pockets (some goes to China but that's the way the cookie crumbles), and so on.
The idea of an independent Europe is laughable, it was happening but in too weak a way to ever succeed and the us sabotaged it easily and will again. After Ukraine the US is going to use Taiwan as an issue, there will be a big thing about it declaring independence, Europe will of course have to "stand with European values and democracy" and antagonize China and commit more economic suicide in decoupling from China to abide by US suggested sanctions, and so on. Europe is cooked. They're going to go to the hard right parties after that happens since the left is not allowed at which point they'll either start doing imperialism with the US while brutalizing migrants or they might actually take a more skeptical stance against the US and adopt a more mercenary position under the banner of white supremacy and reaction. Either way I'm sorry to say I don't see socialism in Europe this decade or probably even the 2030s.