The reason for 400W+ cooler is very simple. According to review by PCgamer, their 10900K consumes peak of 331W.
Assuming you are using a 331W rated peltier, what happens is that the hot at cold side of the peltier will have 0 temp difference. So, its as good as not using peltier. Then, 331W from peltier and 331W from CPU, you get 662W of heat......
In order for peltier to work, you need one that is much higher than the peak power consumption of your CPU. If its lower, your CPU will overheat instead.
You can prevent condensation by controlling the power to the peltier. Long ago, it was done using a thermal probe, but since CPUS all have internal temp sensor, that can be used instead (likely through USB).
One more thing to take note, if your CPU achieves the same clockspeed with or without peltier, then having peltier makes no sense right? So, you want to go higher using a peltier, this means even higher power consumption... so even bigger peltier needed.