You very simply lack the experience and mindset to understand.
There are untrained attackers, common street thugs.
There are those with a little training.
There are those who train in some art, but not yours
There are those who train in your art.
Against the first 2, common skills will work.
Against the third, you must up your game.
Against the last, you must be a true artist.
Part of what he teaches is very traditional. It is the passing down and preservation of techniques, that as taught, are not of immediate use today. But there is a need to preserve knowledge as so much is lost to us each year. Sport fighters do not need this. It would distract them, confuse them, and lessen their sport-fighting game. Ken Shamrock has no need to know how to defend against an armour wearing sword swinging attacker.
Part of what he teaches will work, in the street, if needed. But, why would I use the fancy stuff, if a right hook is all it takes to plant your lame *** out?
Do you understand, or must I get a smaller spoon?