Nice points about the mobile Python. My old company ported Python to Symbian operating system (Nokia phones) around 2008. The problem for Python in mobile is the same as for JavaScript / React Native: The startup time is slow because modules cannot be imported or statically loaded fast.
Even though mobile phones have gotten fast, this is an severe issue with React Native apps. And Facebook is pouring in a lot of engineering to tackle it. But the progress is incremental at the best. As a result some code gets rewritten in C++ because of this issue (see e.g. Trust Wallet). Even though I love Python as a programming language I would not recommend it for consumer grade mobile application development and I feel it is unlikely to get there ever unless some breakthrough happens in runtime development.