If we are the only ones imposing climate regulation, businesses and industries will move abroad where it's cheaper to operate

What are you even talking about exactly. EU regulations for what cars are allowed will be exactly the same whether the cars are manufactured in the EU or elsewhere. And carmakers already have different factories in different regions of the world to serve each market.

Honestly, without some strict rules for European and US car manufacturers to get their shit together, they're only going to fall ever further behind China, which has the biggest EV manufacturer already. Fossil fuel burning combustion engines don't have any future anyway, because fossil fuels are finite, the climate crisis is accelerating ever further and EV are getting more and more competitive (they're already cheaper in the long run for mid and higher class cars). Carmakers aren't being done any favours by allowing them to drag their feet and become ever more obsolete.

Scrapping the green deal is the worst case scenario. Because it's a very weak attempt to start with. It's too littke, too late as is.

Business as usual will cost many times as much.

Forget the economy. There's more at stake than the f*ing automotive industry!

You are completely ignoring, that the automotive industries could have seen the writing on the wall and switch to engineering electric vehicles years ago. They didn't because they were complacent and now they are in trouble, because Tesla and the Chinese are leading the market. It's the industries mindset of "if we fuck up, the government is gonna bail us out, because it needs our economic power", that lead us into this problem.