Think Pod volt light isn't 194 but any small bulb w/ ~ same Ω curve will do same job.
While I & L for CS or B for SI wires and a lot of other wires doesn't carry a lot of amps... 18ga wire is physically stronger then smaller wires and won't break easily.
Is part of why GM and others often have min wire size. Plus is near always Stranded wire not Solid wire.
Then add most are "105°C" or higher temp rated wire so insulation won't melt in the engine bay etc. Most wire types sold at retail including auto parts stores are not rated to handle high temps and big problems w/ temps > 150°F and many even less that that.
Even cabin temps can see 150 to 200°F parked outside in Minutes and doesn't need hot weather to have this.
"105°C" is "Standard" for Building construction and other things but should get the idea across to most.
High Temp is part of "Plenum" wiring rating so resistance to short out when hot plus won't keep burning when external fire/heat is removed. Many Net and Phone installers and more have used Plenum rated wires.
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Dr. Ian Malcolm: Yeah, but your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should.
(Jurassic Park)
The Ogre's Fiero Cave