There is only one answer, like it or not:
Tesla Model S.
I'm not 100% certain yet that the whole industry will go electric, but it certainly seems plausible. Would that have happened, would the entire industry be moving that way if not for the model S? Absolutely not. In the same way that Pagani landed a solid jab into the exotic car space with the Zonda (though, where were they in the 10s?) Tesla broke into the luxury sedan space in a way most upstarts can only dream of. How do you go from nothing to the most desirable product (at least for upper management FinTech dads) with your first offering? Tesla as a status symbol is probably its biggest achievement. Lexus, Audi, and even BMW spent years, if not decades trying to get to the position Tesla found itself in almost immediately.
There's been some other notable cars, sure. The Porsche 918 is probably the most memorable Supercar of the decade (sorry Mclaren, you're doing it wrong) for it's superb integration of hybrid power and it's singular identity - they didn't make a faster one or a myriad of special editions. It just was the 918 and it will always be more special for that.
The BRZ/FRS/86 are notable...but only because they are effectively 90s-mentality cars you can buy today. Not really moving the game even if they are actually great.
The Honda CR-Z could have been great (and I think it's actually pretty awesome as-is) but Honda didn't give it enough love or wasn't confident enough in the formula to keep at it. I would really like to see another attempt in that "small hybrid sports car" space. I'm particularly interested in Mazda giving this a shot with either the MX-5 or some RX-thing. A rotary-electric hybrid could be a spectacular powertrain.
Also: Toyota Trucks. You can't really say this was an active effort by Toyota...but the '10s became the decade when Toyota trucks reached some sort of spiritual supremacy. Combination of good construction and reliability? I suppose that's all you need. Somehow everyone that was into sport compacts in the '00s now is into 4Runners and Tacomas. (Anecdotally, a friend of mine used to have a drift shop [pre 2012], which briefly became a Miata shop, and is now firmly a Toyota 4x4 shop). I feel like there is something in there about showing off and being part of the it crowd.
Special Mention: The Porsche 911. Something flipped after the financial crisis. While before it, 911s were always seen as the kind of rough instrument for speed and not as desirable as something like a Ferrari. But after the GFC, that kind of under-rated nature suddenly became truly desirable. The also-ran became the object of desire to a shocking extent. The workhorse became more appreciated than the thoroughbred. I think this might also be why vintage 4x4s have skyrocketed.