You might notice it to some degree but it's often difficult to reflect back on how you used to play and how you may have improved over time because many of those gameplay adaptations that the higher level of play should have forced you to make will be implicit rather than explicit.
Even then, due to the scoreboard system its difficult to deduce your own individual impact on the game and its outcome. Perhaps you're just progressing because your allies have been performing well, that's often unclear. As for your opponents, even at higher levels, games have their ups and downs, and bad players make their way (somehow) into higher ranked matches, or people do not play their main characters, etc, etc. so it's difficult to deduce the level of play and how it might have changed from say, 20 matches ago, in my opinion.
I usually get gold eliminations, and I get play of the game very often, yet still, we often lose, and even when we win, it's hard for me to know if it's me that has had any real impact. Especially as a Genji player. I kill supports and others, but from one game to the next I will perform just as well, yet one of those games we win, and one we lose. It makes it feel inconsequential.
The asynchronous nature of gameplay across different characters in this game does not help things either as I target characters who are favourable matchups for my character. You could be one of the best bastions or torbjorns in the world but you are unlikely to beat a decent Genji head to head. Again, that's another factor that makes it difficult to detect the variance in oppositions skill level as the fights I pick usually have their outcome determined by the decision making process more so than individual skill and moment to moment gameplay. Not only that, but teams as a whole compose the efficacy of the opposing team, and with my team being variable (different players) it's hard to tell if our collective performance is getting better or worse, and that has obvious cascading effects on individual performance too, which in itself, is to some degree character dependent.
The point is, there are a lot of confounds when trying to make an assessment of your own abilities and how you may have improved relative to your previous performance and your opposition. These blur the lines and make genuinely meaningful progression of your skill both as an individual and team, hard to detect and dissociate. More transparency to the games statistical systems would really help with that.