What if you substituted "steel" with "asbestos" in your argument.
Yeah but well you see, humans did not go extinct from just asbestos!
Asbestos, lead paint, cigarettes, heroin(perscribed generously for basically whatever the doc felt like), "Radithor" (patent medicine containing radium-226 and 228, marketed as a "perpetual sunshine" energy tonic and cure for over 150 diseases), bloodletting, mercury treatments for syphilis, tobacco smoke enemas (yep that was a real thing), milk-based blood transfusions.
Didn't understand those either and used the fuck out of them because "the experts" said we should.
Steel has almost always (as in 99.99...% of the time) delivered to our expectations based on our understanding of it.
The cases where we built something out of steel and it failed are _massively_ outnumbered by the instances where we used it where/when suitable. If we built something in steel and it failed/someone died we stopped doing that pretty soon after.