Right now, to reset overwritten default brush presets, you have to access a specific folder in a file manager and delete a specific file. This is vaguely OK on desktop OSs because this process doesn’t require special permissions there.
But, on Android, it requires installing a third-party file manager like ZArchiver and giving it full filesystem and APP INSTALLATION privileges. (Without these permissions, the third-party file manager cannot access the app’s directory tree.)
These are not acceptable requirements for a workaround to undo an easy accident, and there needs to be a built-in way to reset overwritten default brush presets.

