It's not just you, according to the developer on discord the MMR system isn't finished yet and isn't working properly. There's usually a skill gap in matches and it's pretty common to see people that are clearly better than everyone else and rack up 20+ kills.
It hasn't been too bad on my end, most of my games don't feel too unfair. Sometimes though a game is just over 20 minutes in due to snowballing. I also did feel like games got better the more I played so it might be that it evens out over time.