We don't have to worry about the future of analog IC's designer. Every circuit needs interfaces to the external world.
These interfaces could be in several field mentionned above:
- MEMs or biomedics which interface electronics with mechanical or biological fields
- ADC/DAC that interfaces digital and analog
- RFIC's for wireless applications (everything tends to be wireless nowadays)
- Power Management which relates to the power efficiency of the more and more complex circuits that comes to the market.
As long as the real world will be continuous, which must last a few more years, there will always be a need for analog ICs, and even a growing demand for state-of the art analog interfaces.