Build one yourself, and you will see. LoL! :-D
First of all, a 50K lumens handheld light? You mean something easy to carry in a single hand, and able to provide 50K lumens for some minimum amount of useful time without blowing up or burning the bearer's hand?
You forgot to say “high CRI”, it's too easy :-D that way. At ≈100 lumens per watt ≈500W of output power would be required, which already is ludicrous enough. And concerning the “oscillating phase shifting variable frequency pulsed output mode”, do you mean multiple or variable frequency strobe modes? Strobe mode, a popular thing around here LoL.
Just take a look at this “just 30K lumen” Lumintop BLF GT4 4x XHP70.2 flashlight, which of course is quite a handheld thing (irony). And it ain't high CRI.