The Mazda RX-7 was a Japanese-built 2-seater sports car that had good longevity; it was built over three different decades, from 1978 until 2002. The RX-7 had something that no other production sports car had. What was the unique feature of the RX-7?

Correct!

It had the Wankel rotary engine, known for it's high power-to-weight ratio, but a fuel-hungry motor.

Sorry, you are incorrect.

It had the rotary Wankel engine, known for it's high power-to-weight ratio. Among others, Buick and Porsche offered turbo versions, 2+2 seating was available in the Jaguar E-type, the Nissan 300ZX, the Chevrolet Camaro and Monza, the Ford Mustang, the Pontiac Firebird, and the Porsche. The Mazda Miata and Mercedees 350SL had a removable hardtop.

https://en.wikipedia.org/wiki/Mopar