The US CHIPS Act is getting companies to build fabs in the US. Those fabs will be mass producing chips starting in ~2024-2025. Until then, reduced output of Chinese chips would definitely affect the economy, particularly for industries that use lower-end chips (e.g. automobiles). Restrictions on manufacturing/assembly of devices in China would hurt more industries in the US, but most of that is negligible. If China were to attack Taiwan, that would tank the US economy probably worse than the great recession, but not as bad as the great depression. It would also probably start WWIII, and at that point, theoreticals go out the window. Literally no one knows what would happen at that point.

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