A full scale nuclear war and the resulting fallout would be unimagineably devastating. Whether that kills 100% of humans or only 99.99% doesn't really matter. The natural world we rely on would be obliterated along with us. There would be no remaining governments or modern technology. Rebuilding an advanced society in a
post apocalyptic wasteland would take an incredibly long time, if it's even possible.
Even then, the question would be "Should we?". If our current society ends by violently destroying virtually all life on the planet it will have been the biggest failure of a culture in history by a huge margin. Any survivors might very well develop some incredibly strong prohibitions against unchecked technological change.
Yes nuclear war is very scary. Yes it would be catastrophic to the ecosphere and human society. It is also incredibly unlikely that it would result in the extinction of humans. Also the idea that a post-collapse society would have some taboo against technology is possible but even if true would not hold for long or be particularly widespread. Any group who abandoned that taboo would quickly become more powerful than those who didnt.
Heres some good reading on post collapse society and extinction talked about more in depth. Long story short theres been lots of exaggeration and fear mongering about nuclear war. Clearly its apocalyptic and we dont need to exaggerate anything about it to make it scary. Its already scary. It would be better to have realistic conversations about this.
Even then, the question would be "Should we?". If our current society ends by violently destroying virtually all life on the planet it will have been the biggest failure of a culture in history by a huge margin. Any survivors might very well develop some incredibly strong prohibitions against unchecked technological change.