Yes, I’ve been on here complaining about this same thing.
Keep playing and you will improve. I find the skill gap to bust in to a new rank (Dimond to Onyx) requires a constant average of at least 20 kills per game. To really climb you need to drop 30-40 kill games every now and then.
Otherwise, you will be locked in to your rank and yes this can make things feel very frustrating and dull….especially without any other notable things to progress/achieve.
I keep playing because I enjoy the skill grind. Although I find the rank system very frustrating, it is in fact making me become a better player.
The best tip is to focus on what you can do to increase kill counts during games…don’t focus on the CSR bar it will drive you crazy because there is a hidden MMR ranking that actually has more influence than the CSR.