You'd never know it from reading Bike Forums, but steel bikes are a very small part of the market, and for good reasons. Manufacturers predominantly use aluminum because that material enables the design of frames that are light and yet have a low failure rate (making lifetime frame warranties a reasonable proposition from their point of view). Building steel frames that are nearly as light and nearly as durable is much more difficult.
Discussions of frame materials on Bike Forums tend to devolve into increasingly emotional assertions supported by evidence that is anecdotal at best. That's not surprising; given how costly destructive testing of bikes is, there's not much out there in the way of factual evidence demonstrating the real differences in reliability between frame materials.
However, the German bike magazine Tour once ran an article reporting the results of extensive fatigue testing of a dozen high-end steel, titanium, aluminum, and carbon fiber frames.
TLDR: all of the steel and titanium frames failed; most of the aluminum and carbon frames survived. (The article is hosted on the website of the late, great Sheldon Brown, source of much invaluable and reliable bike information.)
To read the article, do a search using the following phrase:
12 High-End Frames in the EFBe Fatigue Test
Last edited by Trakhak; 10-12-19 at 09:27 AM.