Actually there's a reason behind ICE's still being the primary mode of propulsion of automobiles after more than a century. For instance, battery technology still has a long way to go before electric cars become really practical; hydrogen power is still in its infancy (relatively), and then there's the whole issue of fuel infrastructure. Etc etc... The simple fact of the matter is that looking at the overall picture, the ICE is still the best option out there...which is why it's stuck around for so long, and will be around for a long time to come...
And well there's a reason that the Wankel didn't catch on either...true it's vastly superior to the your run-of-the-mill piston engine in terms of smoothness, high-end power and simplicity. But there are flaws which are inherent to the very nature of how it operates that you can't really overcome...like the lack of low-down torque, and the relatively low engine efficiency due to lack of proper sealing around the rotor.