Since Jesus came, his blood is the only blood that matters.
God says so.
Make no mistake...it was His blood that only mattered long before He came and was killed. That other blood only mattered because it foreshadowing Him and was symbolic of faith and obedience.
Caino is arguing that all these blood letting sacrifices were man made rituals and ceremonies.
But is was never the blood itself or the burning flesh that took away sin or cleansed or purified LITERALLY but that we obeyed His instructions literally...and He was pleased by the faith that was proven by it. "Rather mercy than sacrifice"
Even the Israelites idolized these forms and functions and made too much of them...by taking the ark of the covenant into battle with them thinking it would be a magic ray gun they could use...the bronze serpent worshipped long after its function over being another example.
The shedding of blood (nevermind it was for unintentional sins)was ALWAYS only symbolic until the One Who "takes away the sin of the world"actually did so. And John wasn't wrong, because He shed His own blood and was innocent, He will at the end actually destroy sin and any stained with it...taking it away...