You appear to be confusing first hand experience with some kind of theoretical misunderstanding of why shit gets thrown away. I used a 70s toaster in the 70s, know how their made, etc. Likewise I've closely examined a number of more modern toasters over the decades. Without exception newer models come with noticeably flimsier internal springs and locking components, thinner heating elements and cords, and less durable housing materials. If you're convinced you can engineer a product out of substandard parts and materials and expect durability to remain unaffected I might have a few questions.