> All the roadblocks to Canadian trade with the EU today (especially around resources) are internal to Canada and have nothing at all to do with EU status.

Presumably under the proposed thing Canada would largely adopt EU regulations. This would make trade (particularly for small businesses) _far_ easier. See the UK for how difficult this can become if you're not in alignment; it's survivable for huge companies (though even some of them had trouble; for instance Marks and Spencers' stores in Ireland literally went empty for a while because they were insufficiently prepared), but if you're a small business importing a bunch of components from Europe and making a thing which is largely sold to Europe, there's a _massive_ difference in bureaucratic overhead between being in and out.

Even many Norwegian SMEs don't see direct sales to Europe as worth the overhead, and Norway's in the EEA, as close to the EU as you can get without actually being in it.

> Presumably under the proposed thing Canada would largely adopt EU regulations.

Canadian provinces do not agree with each other about trade regulations. They will not surrender this to the federal government, and they certainly won't to the EU.

Canada isn't actually a single market itself.