That's not wrong, but it isn't the full picture either.
Access to the US market has other values. If the manufacturer is carrying USD denominated debt, they or someone else must obtain those dollars through trade. Access to a large market may unlock economies of scale for producers. Losing access may drive up their overall costs to serve other markets.
These are just two of the most obvious things which I can immediately think of. There are likely other factors as well.
But that's the thing: they don't lose access. To lose access they'd have to actually be undercut by local producers, or untarriffed competitors. They experience the effect wholly through demand modification - and simply ship whatever orders come in, with some pressure to keep lowering prices if they can. It's a tarrif - not sanctions.