My Custom Water Loop is Running Hot, Any Tips to Improve Temps?

Hey everyone! I've got a rig with an RTX 3090 Ti and a 13900K that I haven't overclocked. Depending on the game, my temperatures are running pretty high. For instance, while playing Marvel Rivals, my GPU hits 70-80 degrees Celsius and my CPU reaches 85-90 degrees. I just finished setting up a custom water cooling loop, and I was expecting better temperature performance. I have a LIAN Li O11 Dynamic Mini case with the side fans configured as intakes, the bottom fans also as intakes, and the top ones as exhausts. I opted not to have a rear fan since my GPU is mounted vertically. Is there something I might have overlooked, or do these components just run hot regardless of the cooling solution?