System Settings > Display and Monitor > Compositor > Animation speed The Animation speed slider has 7 steps (0-6). Default is 4, maybe the most balanced option for fast interaction and smooth animation. Value 7 is extremely slow and I guess nobody will use the option. Value 5 is smoother but still too slow for me. However, here isn't an option of 4.5. I hope it can support more detailed control. For example, 20 steps. And the slowest speed may not be that slow if it is not practical for daily use.
I'm sorry but it's too much effort for too little gain.