I'm also bothered by the unavailability of a replacement brake pad. Why are brake pads not interchangeable between cars anyway? I understand there are different sizes and stuff, but a few standard types like there are for tires, windshield wiper blades, and other consumables should be enough. Tesla looks pretty stupid in this story.
Tesla is known for its NIH syndrome, but I think the reason for better parts availability with other brands is also because they have far more models and an appreciation for working at that scale, so tend to use no bespoke parts unless absolutely necessary.
I agree that these well-known wear parts parts should be standardised. There's no need for each model of car to have slightly different brake pads.
There are also entire companies like Bendix which specialise in braking systems (and may be most known for the vacuum boosters for a ton of vehicles).
(I made the same comment here but got downvoted too. Maybe by some designer who thinks they need to be "unique".)
