Yes, you need evidence lol. Yes.
Thank you for confirming my point though.
Do you really go through life seeing confirmation of all your beliefs everywhere, without ever checking?
US consumers spend about $115 Billion annually on wine. Exports to canada are less than 1% of that. I don't see how Canada matters much to the US in general, and specifically it doesn't make sense that a 70% reduction in half a percent of wine sales (that's like 0.4% reduction overall) is a major factor in putting the industry out of business, but you are welcome to look it up yourself or correct me. Keep in mind that US wine sold in canada will have gone through several hands and be heavily taxed, so the amount per bottle getting back to grape growers is a very small percentage of that already tiny percentage.
But of course you won't bother to look it up, you will just roll your eyes and assume US grape growers are being forced out of business because Manitoba's liquor stores are finally flexing their international influence!