Well one difference is that patents only have a lifespan of what 20 years or so? Most of the basic tech in a car that was patented in the 1900's is free to be used and improved upon. Is new stuff patented and licensed? Yes, absolutely it is.
Notice how Toyota partnered with Tesla motors to build an EV SUV? Or what about how Ford licensed Toyota's hybrid technology back in 2004? Patents and licensing.
Given that the automotive industry is much older than the computer industry, they've likely learned the value in licensing technology where it makes sense. Nobody would claim or confuse a Ford Fusion Hybrid with a Toyota Prius.
Also, Ford, Chevy, Toyota, Hyundai, Honda, etc. all by now have fairly distinct branding and styles, so you don't see as much where the new Ford sedan looks just like the new Chevy sedan in hopes of selling more vehicles.
Samsung seems to have made a real effort to look and sell as if they're selling iPhones and iPads. That is why they're in trouble. Notice that Apple didn't sue Blackberry for the the Storm or the Torch looking the same as the iPhone.