Hi,
VM 4.0.0 on J3.10.8, when updating install error "Call to undefined method TableProducts::setDateFields()" back to update, this time everything looks ok but 6 countries (Isle of Man, Guernsey, South Sudan, Curaçao, Montenegro and Åland Islands) published by default :)
Tested on 4 websites
Added countries are published by default, yes. But your old unpublished countries should keep unpublished