There are two probable reasons for Toyota opting not to phase out the older Innova in the Philippines; at least not yet. The first reason is likely because they are not looking at retooling the local assembly plant for the new model. Going to an entirely new platform (frame-based to monocoque) entails a totally new assembly process, and that takes time and a lot of reinvestment to do. And being a hybrid also means they have to invest in the equipment to assemble that too.
The second reason is that customers would probably want a turbodiesel for a seven (or eight) seater like an Innova, and the non-hybrid variants are using 2.0L gasoline engines. And as it stands, we have yet to see a turbodiesel on the third-generation model as the diesels are rear-drive oriented. And of course, diesels have largely fallen out of favor in many of Toyota’s markets… except the Philippines.