I'm not sure economic hardship is pretty funny, but I guess we all have a different sense is humour.
The economic situation isn't static and tariffs are a tool designed to preserve or restore a competitive advantage and protect existing manufacturing, not bring back that which has been gone for decades. If a product or class of product that used to be manufactured in one place moves, there's a finite amount of time where protectionism can save it.
In Canada and the US, we have access to almost everything required to build cars at competitive prices when compared to everywhere else in the world. But increasingly we're seeing vehicle manufacturing get outsourced to places that have a competitive advantage in labour costs. While that advantage is only labour, a strategic use of tariffs could protect and preserve manufacturing because there is still near parity in competitive advantage. But it you wait until all the manufacturing jobs have left, the workforce has moved on, the factories have been gutted and torn down, and the manufacture of inputs has also relocated, then the tariffs cease to be useful at bringing the jobs here because startup costs become prohibitively expensive. Companies will wait out the tariffs, knowing a shift in political climate will almost certainly happen faster than the manufacturing capacity can be restored, and once these happens the balance to competitive advantage is lost and it become cheaper to shut it all down again.
Remember when Trump put tariffs on Canadian steel and as a result almost everything manufactured in the US that involved steel got more expensive? He did it claiming he was going to protect US steel manufacturing, but it turns out US steel couldn't meet production demands. They didn't really ramp up production either, because while they have a competitive advantage for existing demand, expansion costs were prohibitive. And so as a result he eventually carved out a bunch of exemptions, rendering the entire exercise mostly moot, but only after damage to both our economies had been done. It didn't reduce inflation, make things made of steel cheaper, protect manufacturing, or bring jobs back. It drove up prices (which still haven't come back down fully) and increased inflation while saving no jobs and creating no extra.
In fact, the tariffs implemented by Trump during his last presidency are estimated to have resulted in a net loss of 160,000 jobs, and because portions of it impacted critical industries that needed to be preserved (ie the farming industry as a result of his soybean tariff), it cost taxpayers a fortune in subsidies.
The reality of free trade and competitive advantage is complex and there's a lot of nuance. It's not that tariffs are bad, it's that a guy who clearly doesn't understand them and has a history of implementing them to the detriment of the economy is saying he's going to use blanket tariffs to restore and punish, rather than to protect, and that's not how tariffs work.
He's selling a strong economy via tariffs but that's not reality. He's actually touting a trade war while claiming it's going to reduce inflation and bring back jobs, and that has never been the goal or result of any trade war.
So no, it's not that tariffs used to be good but now they're bad. It's about acknowledging that tariffs are a tool and like any tool, it can be used wisely or poorly, and both Trump's words and past actions make it clear this is going to be the latter.