I formulated this to myself as not a concept of absolutes, but relatively. A couple of decades ago when I worked interim for a Canadian high-end industrial tool manufacturer, not just the proximity, but the NAFTA-enabled barrier-free trade was making the US a powerful market. When a US customer asked for something, we'd pay much more attention to it than when a European customer would, because it was easier to do business and to sell a particular requirement to more than just one client.

Nowadays, Canada has a better treaty, from the ease-of-business (and reliability) perspective, with the EU than with the US (mostly because all the insane EU laws are anyway present in Canada, so there's no real additional friction there.) I can totally imagine that solutions get more and more tailored to European ideas and requirements as trade with Europe grows relatively to the US in that organization - maybe I should travel to ON, have some beers, and find out - and that is a slow path to decreasing US business because the product will start to slowly fit less into the US market demands - though note that this would require not 3 months but a decade or so of the same decisions we've seen recently.

The more barriers to trade you erect, the more isolated you'll become. This is a slow process though, and 3 months or a year of uncertainty can be overcome, except for those that are leveraged too much.