For gaming and streaming, 16GB is enough for now.
You will need 32GB or more for something else e.g. heavy video editing, etc.
You can see up to 12GB but never exceeds 16GB yes? Some games can really use up or even more than 8GB for it alone (The RAM management in OS and the game will take care how much will be used acoordingly to how much you have), you have then the usual Windows stuffs.
This should be still normal, if you mainly only game.
I would however still check if there are unnecessary background apps running or viruses or whatever...just to be sure
So, I would not go to 32GB.
1. You do not really need it.
2. RAM price is high at the moment.