It's built with old-fashioned materials and technology that are expensive to duplicate and toxic to manufacture.

For some reason, vinyl records and safety razors have come back into fashion, but your toaster hasn't.

It is mostly constructed of stamped sheet metal and toasters to this day primarily use nichrome heating elements. The lever arm mechanism is probably the most difficult part, but I saw nothing in this construction that would be toxic. The original design is ungrounded and wouldn't pass safety certification, but there is even a linked video for how to modify the old Sunbeams to use a 3-prong cord.

To me, the beauty of this design is that these toasters apparently work for decades because they were well-designed to accommodate the tolerances of the materials and construction methods and they are essentially purely mechanical.

There are a number of expensive automatic toasters available that utilize some combination of sensor and motor to raise and lower bread. They all seem to have mediocre reviews. I don't think these are necessarily inferior in design to the 1950s Sunbeam, but unlike the appliances of that era they are built to be disposable. A Chinese clone of a Sunbeam Automatic Toaster would also probably be a failure because it would be built to maximize profit on a 2 year lifespan...

Safety razors are great, and actually much cheaper and gives better shaves than cartridges.

Plus it's just fun to use.

I've had two over the years at share houses, both found on the side of the road. Worked generally OK, but sometimes burnt the toast. I'm wondering if they were tuned to a specific type of bread, and didn't really handle sourdough. Still see them from time to time in second-hand shops.