....Not entirely sure if you are being sarcastic or not, but on the chance that you are not.
OP is stating that matchmaking is poor since a team made up of gold/plati players got matched into diamond/plati, the second being a much higher tier thus when matched against gold it's not even a match, it's a massacre.
Like, taking a ......Orange/yellow belt martial artist(has studied for a while and learned but is still middle tier) and throwing them up against a full on red/black belt martial artist (just below top or even top tier pro) and telling the middle tier guy that he is supposed to have a fair fight with the pro.
Naturally since both are doing their best the higher tier will just steamroll the lower one, due to a severe difference in experience and training.
Calling that fair and even fight is just about the same as calling the Polish cavalry defense vs german tank and air bomber army in WW2 a fair one.