Not only that but their religion is highly centered around pain, particularly physical pain.
"pray to elevate your pain" and stuff like that. Yuuzhan Vong are basically pain junkies obsessed with bodily/physical pain. For millennia, such high devotion to this and their SEETHING anti-mechanical tech mindset has blinded them to opposing points of view. The Abominor-Silentium War in the distant past that led their original home planet of Yuuzhan'tar(a sentient planet mind you) to be highly damaged via heavy laser blasts and strip-mining left a big festering chip on their shoulder.