Isn’t it possible, given (as far as we know) the 13+ billion years the universe has become a vastly complex thing far beyond human comprehension, and the human brain a vastly complex system, that consciousness, emotion, our concept of ‘soul’ etc are all just output of that system, that we can only interpret as such given our limited ability to understand it? And when the system dies so does our consciousness? I haven’t read the Bhagavad Gita, but this idea doesn’t contradict the piece quoted (which doesn’t specify consciousness) since our atoms were and will be transformed into other things, and given the 1st Law of Thermodynamics says our energy can’t be destroyed.