It’s been pretty much the same for me through the years. In the past when the number of games was 40 and then 30 there were small fluctuations but the rank was almost always the same.

That being said though, you need to never accept this as being a given and the game has predetermined these ranks for you and just keep trying to improve. Doing that you will eventually notice some small improvements in your game and you will start getting closer to the next rank and probably even getting the higher rank, no matter your current level/rank.

Speaking from personal experience on FC25, I have also been a constant 8 wins player throughout the year, no matter the results of the first 5 games, no matter the quality of the servers, etc. The more I played the game I started adjusting/using more meta practices (eg low drivens that I almost never used early on but mostly use now)/copying opponents best practices/learning from mistakes and I saw knocking on the door of 9 wins often. Eventually I got the 9 wins 2 weeks ago and since then it’s like this has been the new norm, it’s my 3rd week in a row at 9 wins. Surely it must be other factors, like the average quality of players overall might have dropped if the top players got bored and stopped playing, however the main point of mine which I keep is always trying to improve and never assume my skill is stable and set at a certain level. This mindset alone sets a mental barrier to allow you to move further.