I think one of the problems of Mercedes was a component which they changed from Bosch to another brand. But it´s true even if they tried to make the cars of the 90´s it wouldn´t be possible. Also at some point because of climate they actually made biodegradable parts. Your buying a car expecting it to disintegrate...Even with good brands/products there’s no guarantee the quality will persist, despite the best intentions, if their subcontractors and suppliers cheap out it’s over. If you find something you like and will need again (clothing, shoes, tool, small appliance, etc.) buy more and store it, a year or two later the “same” item may be produced in a different country or even deeper in China, reviews are replete with “this isn’t like the one I bought before” stories.
I suggest eBay to track down some of these vintage or NOS (new old stock) products, you can set alerts for when new listings are posted. I like Next Door, it’s the best local app I’ve found with a good “for sale & free” section. No one has unlimited space so it’s a good way of selling or getting rid of things (especially bulkier items it’s not worth shipping or paying to dump) so you have some space for quality items. I’ve discovered some cool products this way too, bought a pair of US-made Pendleton shirts for $70. It’s a rarity but I managed to buy four pieces of high-end McIntosh audio equipment for $500 total. I’m not an audiophile so I will sell these for roughly $1000 each.
Networking with people that have similar hobbies and tastes in quality products is important too. If someone knows and likes you they’re far more likely to sell or even give you something of value than someone who’d be willing to pay much more. If you’re really after something that you can’t find you can post ISO (in search of) posts on Next Door, Craigslist or whatever app is best in your area. Yes quality has taken a nosedive but we’ve also never had the ability to search for and find things worldwide. I’m a bibliophile and regularly buy books from international sellers, New Zealand most recently. I always try to reach them directly through their own stores so they aren’t charged a commission and make reasonable offers below their list prices.