Title is a little misleading (for me at least), this is not one of the many cases where a group of young people sued their government for a broad violation of their rights. This is a more narrow case where the plaintiffs said the government is supposed to consider emissions impact when approving oil and gas projects, and did not. There aren't really any youth directly involved. The court didn't say Norway can't drill…
It's not at all obvious.
1) If we assess all the indirect negative impacts that happen in remote places, nothing will ever be done. Should a factory making phones assess the DALY lost by drivers who get into accidents because of distracted driving?
2) Also, if we are going to assess hypothetical impacts of burning oil, why not assess the positive impacts? This oil could be used to build wind turbines, or to deliver food to a famine-impacted areas, or to raise living standards in the developing world. Generally oil is energy and energy is a precursor to GDP and high living standards.
The end result on not developing European (or US) energy reserves is that Europe is going to buy energy from dictators all over the world. Frankly it's one of these cases where I switch to my cynical mode "I hope there's enough civilization left for my lifetime, cause if you are THAT dumb, you deserve to be defeated."