Our friends from PlatfiormIO have released 6.1.0 version of PIO core including significant change:

• Allowed to Import("projenv") in a library extra script (issue #4305)

This feature removed requirement to manually unflag -fno-rtti, all is now handled by fix_rtti.py script.

https://docs.platformio.org/en/latest/core/history.html
https://community.platformio.org/t/force-rtti-from-library/28176

Another amazing thing, that since I've moved with ksIotFrameworkLib towards PlatformIO, CICD became easy.

Currently all my three projects based on this framework can be built on github with Github Actions, producing firmware binary file ready to be flashed on the device. This can be done even with mobile phone (as user can trigger Wifi Manager portal and then upload downloaded firmware file).

Next step is to use CICD features to implement unit tests for framework library :)