My guess is this: Mazda believes its battery-only range is enough for most driving situations. If they're right, the rotary engine's more limited lifespan would be a moot point since it will still last the vehicle's entire lifetime. One can only hope.
The maintenance thing is concerning, though. Nobody knows how to work on these things. As an RX-7 or RX-8 owner, you're either doing most of your engine work by yourself, or you're driving very long distances to go to a specialty shop. We can pray that it's reliable enough for this to not be a problem, but if these engines start failing, it's going to be a huge mess.
Side note - the geometry of a Wankel rotary engine makes a diesel version impossible - you can't get enough compression. Diesel rotaries do exist though. An American company called Liquid Piston is making them for the Army. The intent is to use them in diesel generators, since the resulting generator is much smaller and lighter than more traditional diesel generators.
The maintenance thing is concerning, though. Nobody knows how to work on these things. As an RX-7 or RX-8 owner, you're either doing most of your engine work by yourself, or you're driving very long distances to go to a specialty shop. We can pray that it's reliable enough for this to not be a problem, but if these engines start failing, it's going to be a huge mess.
Side note - the geometry of a Wankel rotary engine makes a diesel version impossible - you can't get enough compression. Diesel rotaries do exist though. An American company called Liquid Piston is making them for the Army. The intent is to use them in diesel generators, since the resulting generator is much smaller and lighter than more traditional diesel generators.