To clarify slightly: it shows the old gear is significantly heavier in three areas: head, hands, and ‘accessories’. I think that suggests where investment in technical fabric has been most successful at improving the burden of mass in surviving extreme cold.
Tech fabrics were a prerequisite to the widespread use of down in adventure clothing. Earlier fabrics were either too heavy, like leather, and would collapse the down and negate its insulating properties, or would get wet like cotton/linen and saturate the down.