I was always under the impression it was less about red tape and more about safety standards. Most foreign cars do not meet the safety standards required in the US/EU. My favorite example is in Mexico, Toyota had a model that was more or less the same style of an early 90s Toyota. You could still buy them new in ~2016, they had no upgrades to safety etc, you would never be able to sell them in the US.

I remember vaguely on one Chinese car in Eastern Europe cca 1 year ago, which was cheapish, but made from cheap plastics, squeaking, infotainment was booting 30 seconds and ICE engine, despite its relatively small volume was taking 10 liters per 100km. I don't think that they have sold many of them.