Exactly, weight is not everything. Weight distribution is equally if not more important when it comes to comfort. The size, thickness, depth and filling of the earpads, appropriate clamping force, decent headband width and padding all play a role. ZMF BBB strap for example helps a lot with weight distribution and level of comfort.
My 560g Caldera open feels significantly more comfortable to me than the 523g Final D8000 or 490g Utopia. Similarly, I never had issues with the 550g Audeze LCD2C, mostly due to the huge and super comfy earpads. I would say the LCD2C is more comfortable than the 375g Denon D9200 (which is not bad, just not great either).
My point is that you cannot judge comfort by weight only. ZMF headphones are comfortable. Perhaps not as much as the 430g Meze Elite or 415g DCA Stealth, but certainly in the upper third or even upper fifth of headphone brands. And that uniquely organic and engaging sound will make you forget every weight concern you previously had anyway.