I think one possible resolution for increasing the popularity of RTS is to take a hybrid real time approach. You can build and do things in real time, but under the hood battles and the economy operate in discrete chunks of at least several seconds.

Come to think of it, I saw two approaches that were similar to this before:

1. In Frozen Synapse, you plan your turn, eventually commit it, then it plays out at the same time as the enemy planned turn. You can even move enemy units while planning to simulate possible movements and attacks they might make.
2. In the fourth Battle Isle game, Battle Isle The Andosia War, you did your strategic turns with your units, then in real-time as everyone else did those turns, built your production base and produced units. So the longer you take for your strategic turn, the more time everyone else gets to work on their economy.