You are completely and utterly wrong. Yet you continue. Amazing.
And you're not the first to distract with claims that it is someone else's ignorance.
The P20 Pro does image stacking. Period. That is exactly what this new Pixel mode does. In actual results the P20 Pro is better.
I'm not the person you've been talking to, but I don't think I'd agree with that statement. To take the video you linked earlier for example, the Pixel frequently gives better results. For example, this one shot https://youtu.be/wBKHnKkNSyw?t=227
Note that the Pixel 2 has a much smaller sensor, and the exposure time on the P20 is 18 times longer, and yet the Pixel generates a much better sharper image. What you're saying is correct, that the P20 is using some very advanced image stabilization to get results that good from 6 seconds of data, but the Pixel seems to clearly offer more advanced software.
Further, you're reading entirely too much into the exposure times. They are artificial and either camera software can choose to put whatever number they want in there. The aggregate time. The average time. The theoretical equivalent time. Etc. It is not the actual times.
I took actual photos with the pixel 2, and I know the actual time taken. It's less than 3 seconds every time. By all accounts and reviews I've seen, the P20 is 10-25 seconds. Show me a review saying otherwise.
This thread is dominated by Pixel...fanboys and Googlers. You can be as wrong as you like, it doesn't really bother me. But your bull headedness about your absolute wrongness is simply spectacular.