World War 2 took at most about a decade (depending on who you ask). The history of development of our technology is much, much longer. I doubt 'most of our technology' is based on anything that happened in WW2.

The general sentiment is still true, the reasons for engineering and (often science) are not always nobel (pun intended)

Sure. I'm just objecting to connecting everything to WW2.

It's just that technologies are all connected, so if you want to make them look bad you can do so. Is fixation of nitrogen into ammonia something that improved billions of lives through fertilizer, or something that enabled manufacture of many millions of tons of explosives? It's both.

Sure, no question about that. I'm just objecting to connecting everything to WW2. There were plenty of other wars before and after and even at the same time.