There is a long history of US export restrictions on technologies. They have all been temporary.

It would be extraordinary if this was the beginning of the first ever permanent technology export restriction.

Temporary as in it lasted for quite some years, not temporary as in it was dropped within months. That's a very long timescale for this sort of field.

From outside the US, there has been so much "extraordinary" stuff happening in US politics recently that it's almost expected now.