that is not how tech companies work.. they dont say oh well it hasn't been done so we wont go there.. they say it hasn't been done so we're going to find a way to get it done.. every invention ever created was 'not feasible' until someone came along and brought it to market.. solar powered phones are very very reachable and possible.. if we can send a rocket to Mars and make vehicles that drive themselves while answering our phones calls and googling every question imaginable using AI then we can put solar charging technology into a phone