[MAC] Major Frame Rate Drops and High CPU Usage

I use a late-2016 Macbook Pro with the Touch ID bar, running Mojave 10.14.6 (the latest version before Catalina). During a game, my frame rate will often drop from 60 FPS to between 5 and 15. The problem affects not only the game, but my entire operating system when I tab out. After closing League, my computer's frame rate and operating speed returns to normal.

During an episode, Activity Monitor shows kernal_task using an abnormally high amount of CPU - anywhere between 100% and 300%. This occurs ONLY during League games and sometimes when running the League client on its own - it does not occur while running other (more) graphically/computationally demanding programs/games.

There are others like me experiencing the same issue. I copied the screenshot from this post because mine would look identical: https://boards.na.leagueoflegends.com/en/c/ask-the-community/w9glLObE-please-help-i-cant-play-league-because-kernel-task-uses-too-much-cpu-mac

Thank you very much for taking the time to read and investigate. Please feel free to ask any questions that will help identify the root cause. I hope we can implement a fix soon!

Theo