"Leave voters were lied to. How could they have know Brexit would go so badly?"

Because every household in the country was sent a government booklet in 2016 explaining exactly what would happen if we left the EU.
1/

"But nobody told us prices would go up after Brexit"

Yes they did. The government told you that would happen

"But nobody told us jobs would be lost because of Brexit"

Yes they did. The government told you that would happen:

"But nobody told us the cost of living would go up because of Brexit"

Yes they did. The government told you that would happen:

"But nobody told us Brexit would make it harder to export to the EU after Brexit"

Yes they did. The government told you that would happen: