In the article I linked they weighed the actual bikes used by a selection of 12 or so riders. In your link they appear to have just looked up manufacturer weights.

If you do a lot of competitive hill climbing then weight matters to a certain degree. 9 kg vs 7 kg would cost me maybe 90 seconds up Alpe d’Huez. But on a flatter route it would make hardly any difference at all. That’s why the pros don’t really care about making the UCI min weight for anything other than big mountain days and even then many of them don’t bother changing bikes if they are not climbers. It’s also why most modem frames and wheels are more focused on aero than weight.