First, under all circumstances, natural light is better than flash, because is well....natural. It is real life. Even the best flash only tries to fake naural light.
To not need a flash, you would need a camera that takes in ALL available light. This requires a sensor and lens that are perfect in light conversion efficiency. This doesnt exist.
However sensors and lenses do exist that take take in far better amounts of light than typical stuff. Eg medium format or full frame DSLR sensors - or in the lens arena, lenses that can do F1.4.
Of course phone manufactuers are still fooling phone buyers with sensors the size a phonehole and plastic lenses worth about 5 cents. And then they wave nonsense like "Xenon flash" and people go nuts.
I assure you if they put a better sensor and lens in a phone, you wont care what the flash is. I mean do you ever read digicam websites and see anyone discussing whether their Canon Powershot has Xenon or LED flash? Give me a break.
Moreover, phoen cameras are supposed to be spur-of-the-moment items - the more you can put it a decent lens and senson so you can just take a picture and get on with it, instead of stopping things then wasting time with an innefective flash, the better anyway.
They have folks totally diverted from the issues over here.
Get better lenses and sensors in these things - forget the xenon vs LED nonsense.