Why is matchmaking so bad?

Disclaimer: I know I need to “get better” lol. I’m average, some games perform slightly above average. I make the right passes, play defense, but it’s clear there is just a skill gap roughly 50% of the time. Why haven’t they figured out a better way to fill games yet?

For example (I know just one, but plenty more, just most recent), I made a new build today to try to experiment, again, to get better lol. My team fills with between 62 ovr and 75ovr. Black or bronze plate. I think okay, maybe able to actually play a bit against some equal comp. Nope. Game starts, and the other team is 5 99 overalls, 3 gold, 1 purple, and 1 bronze. As expected, we were down 20 before we could blink.

TLDR: Matchmaking sucks, I suck, 2k is starting to suck for me.