In my personal experience, weight is more of a problem in people's minds. A well-balanced bike with more weight rides much better than a light, unbalanced one. On my Eboxx, for example, I've fitted a front smashpot... The bike is heavier but still rides better. I haven't weighed it myself but yes it probably weighs 27kg. If you're looking for a particularly light bike, Nicolai is the wrong place, but if you're looking for a particularly good bike, you're in the right place
Of course this is just my opinion and if it were possible to build the same good, stable, balanced bike with 4 kilos less I wouldn't have anything against it, but physics is physics. For example, in contrast to the chain, the belt requires a certain stability of the compression struts. Rotwild, for example, had the lightest possible weight in their specifications ... so they use a chain to save material ...
Edit: I am a 188 cm man weighing 115 kilos and have played handball for 30 years ... for me the weight is probably significantly different in handling than for my wife, for example.