If they don’t produce them at that price point, you let China and BYD steamroll them

The problem is that they've already proven themselves unable or unwilling to produce affordable EVs any time this decade, so allowing Chinese competition at any reasonable tariff level will almost definitely doom them. For the government, it's a "damned if you do, damned if you don't". And the automakers are clearly betting that the government will protect them no matter what, even if they're suicidal. When companies like GM or Boeing play chicken with the government, they know the government will swerve first.