There is no oil used in the video that I linked. Did you watch another video?
The water glides across the pan due to the Leidenfrost effect. That’s the point when you add the oil.
I suspect there are some truisms involved here, but the common wisdom is that there is a combination of contractions in microscopic imperfections of the surface of the pan from the heat (more accurately, expansion causing the gaps to close) and the laidenfrost effect keeping the food from sticking once the pan has reached sufficient temperature.
Regardless of the true mechanism, my own experience suggests that most complaints about sticking with stainless steel can be avoided by properly heating the pan before adding the oil and food.
For what it’s worth, here is one manufacturer referencing a porous surface:
Ah, forgive me. I was going off memory and thought you meant during the heat testing portion which only used water for the test.
It seems you take issue with calling it non-stick when oil is involved? To that end, sure, Teflon-like pans beat everything. But I don’t know many people cooking without oil even in Teflon-like pans.
When people say that properly heating a stainless steel pan will allow non-stick cooking there is certainly an implied asterisk involved re: oil. That’s because it is in direct contrast to a cold stainless steel pan which will cause foods to stick even with oil.
The video just shows a nice hot pan with oil in it, no matter the pan's made of, under those conditions of course stuff isn't gonna stick.