I will agree that for the most part, technologies and materials have improved greatly over the past 30 years.  It's the manufacturing processes and material selections that have declined in my opinion.  Manufacturer's are cutting corners with materials and processes to keep overhead costs down and to maintain profit margins.
As one good example, just look at the gear of the past and how they protected pant cuffs from sharp ski edges.  My old TNF gear has 1000d cordura reinforcement panels, and has stood up to more abuse than I could ever imagine.  Trew uses a terribly misnamed "Superfabric" to protect their ski pants...it might as well not even be on there as it has added absolutely no additional protection to the pants.  My Trew pants lasted one powder day before they had numerous cuts through the exterior and interior materials on the pant cuffs.  "Superfabric" my ass...Why change what worked so well in the past?  Costs perhaps?  You can't say that modern materials work better than the past in that regard.
Waterproof, breathable, comfortable...sure, for the most part today's materials will be superior, but does that make them more or less durable?  I never had one single issue with moisture in my 3L Gore Tex TNF gear.  I can't say the same for some of the Gore Tex products I've owned since then.
TNF used to be way more core and dedicated to their customer bases.  Now that every highschool girl and frat boy has a TNF fleece in this season's hottest colors, who do you think they are marketing towards?  Do I honestly need to point any farther than the upcoming jackets with floral hawaiian prints?  That's not to say they don't make nice gear nowadays, but overall their products have been considerably watered down over the years.