Tenzing saved life to Ed, maybe more than once, but specifically once Ed made a careless jump over crevasse in lower parts of the mountains and started falling into it. If you saw photo of both together you must see Ed was almost twice the weight of Tenzing, so quite an effort to catch and save him.

There were some less-than-stellar reactions in media and politics, west mostly ignored Tenzing, in India Ed was ignored completely. You are right, they both needed each other and I think after coming down they knew pretty well how much luck they had to just survive this (ie climbing Hillary steps barely 100m below summit, must have been extreme... now there are permanent ladders installed by Chinese expedition, often a choke point where people get frostbites from long waiting to pass up or down)

...Norgay (who would have died of asphyxiation if he tried the same)

What makes you think that? Many Sherpas climbed Mt. Everest without supplemental oxygen because of their genetic uniqueness. In fact, one did it even 10 (ten!) times without bottled oxygen. Lot of other Sherpas can do the same.

https://omgnepal.com/ang-rita-sherpa-climbed-everest-10-time...

I'm not sure if this is the same guy, but a Sherpa bivouacked overnight at the summit with no oxygen, just to show it can be done. Well, this was word of mouth from a "Khumbhu doctor" (pro route-setter for the Khumbhu ice falls) when I was in the region years ago. The guy he was talking about had summited multiple times, and set all kinds of unofficial speed records for ascent + descent, but was kind of off the radar because he was on the worker side of the industry, not the sponsored climber side.

False equivalence as those summits were achieved after climbing aids like ladders were placed on the third step and other difficult parts of the ascent.