I was thinking of this post:
I don’t know if PIO will go the way of cmake - I can’t imagine that will happen since it provides it’s own build system, which is cross-platform and cross-architecture, as also being zero-configuration to install (unless something goes terribly, terribly wrong)… but that’s up to Ivan. However, judging from the ESP-IDF documentation, I do believe there will be zero effort towards cmake since the developers consider it to be in a preview state until ESP-IDF v4 is released, and PIO does not support non-release versions of toolchains.