Comments by "Theodore Shulman" (@ColonelFredPuntridge) on "Politician Has CRAZY Solution for Catalytic Converter Thefts" video.

Too much toxic emission.
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A technical point: palladium and platinum are NOT rare-earth metals. The rare earth metals are scandium, yttrium, lanthanum, neodymium, praseodymium, dysprosium, terbium, samarium, gadolinium, europium, ytterbium, lutetium, erbium, holmium, thulium, cerium, and promethium. Not gold, platinum, palladium, or rhodium.
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@sophiophile None of the "rare earths" are really rare! What is rare is to find deposits which contain them in useful form from which the metals can be purified. This, by the way, is what we are hoping to get out of Ukraine if we manage to help them win their war: preferred-buyer status on their mining franchises. They have lots of potentially valuable rare-earth deposits; also lithium, neon gas, nickel, and mercury.
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Electric cars don't have catalytic converters, but electric cars do contain a lot of rare earth metals. With the current state of the technology, any device (including an electric car) which converts electrical energy to mechanical energy (or vice versa) requires very strong permanent magnets, which are made with alloys containing a lot of rare earths.
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