The "leavers" you talk to are pretty different from the leavers I talk to.
Well of course, after all there are millions of them so I'm sure it's relatively easy to find people from any part of the "leaver" spectrum - from people who knew exactly what WTO is and are happy with it, to people who voted leave because they don't like the Polish shops on their street.
There isn't a single one reason why people voted leave.
I can't believe anyone would make such an assumption. I know some people who 1) voted leave 2) are perfectly aware that under WTO rules their businesses would literally have to close because they trade with EU and their European partners won't accept a ~20% hike on the price of British products due to non-EU custom duties. They all wanted out of EU because they don't like the immigrants, because they think Brussels has too much power, but they all wanted easy trade with the EU. WTO trade is not what they voted for.