I hung my bike-- in riding condition, with tool pouch, water bottles, etc.-- on the scale at the LBS. 26.5lbs. I did almost 7500 miles on that bike in my first year of riding, with no random mechanical failures, just a handful of flat tires, and one crash. So equipment does matter... but it has absolutely nothing to do with weight.

A lighter bike won't make you a better rider. But it might make you think you are, so it will make you delusional. Then logically,

light bikes = mental illness.

Can't argue logic.