There's no need to return to the troubles unless the EU put up a border. That's on them.Back to this. Any ideas that don't involve breaching international treaties, blowing up the free trade deal with the EU, and all future trade with the US, becoming an international pariah, and a return to the troubles with the death of more British citizens? I get that Boris cares less about NI than you do, and would have no compunction throwing it under the bus again if it served his needs, but he's not about to do anything as utterly stupid and vacuous as you suggest thankfully.
We shouldn't be continuing with treaties that don't suit us. Treaties are only of value when they benefit both sides.
You might think that means the end of trade with the EU, most thought Brexit would but it didn't.