Why is the match making for flex still bad platinum place with silvers?

I don't get how I'm place with silver when I'm platinum in flex and the worst part is this trash match making force me to balance out this system by placing me in a silver-gold team while enemy get gold and plat.

This match making is still so bad in flex that it's hilarious that this is consider rank at all when the odd of this match making is against you. Seriously what kind of crap system places a platinum 3 who solo Q in a flex Q from gold 5 to plat in a match with a team of silver and gold vsing a enemy with more plat and gold player?

Note: They are silver in Flex rank I'm not using their solo Q rank.