I wonder if it would make that much difference in practice. For one, a climb isn’t pure watts per kilo, so that would take a bit of the .024 you’re applying to the climbing time. Probably more importantly, they don’t race at a steady wattage. Say it gives a few seconds at a steady pace up 30 minutes climb at the end of a stage. Roglic can still be in touch and still sprint away from the smaller guys at the end.
On the other hand, cumulative fatigue matters, so maybe it makes the difference between getting away and not. And maybe it makes a couple of seconds difference on days when there are bigger time differences. Or means Roglic doesn’t have enough to sprint.
Who knows! Be interesting to see what happens if the UCI do eventually lower it.
I’d like to see them have a few races where every one gets a bike that weighs 10% of their weight.