Nobody wants to work outside at wages so low.

A co-worker years ago was the son of a construction worker. One winter his father was on a job site in New York, within easy view of an office building. Some of the clerical staff in an office put up a sign in the window: "It's 70 Degrees In Here". The construction workers put up their own sign: "It's $X/hour Out Here", $X being considerably higher than the going wage for clerical workers.

Wow those clerical workers are assholes.

Ya, these obviously fake class-warfare anecdotes are weird.

People retell and repost them as if they were real, despite being obviously made up to show group X being bad/dumb/naive and group Y being good/smart/wise.

that's exactly it. Of course there will be some people who turn their nose at outdoor construction work, but the much bigger reason is the pay is just not livable. In KY the average pay for a construction worker is $14 an hour. You can't buy a house or raise a family with that.

From what I can tell of labour history, 1921 would actually be /after/ most of the increases in labour safety and labour standards. The gap between 1871 and 1921 on that one is probably bigger than 1921 and 2021. The 48 or 40 hour week was long established by 1921 while 80 hr was standard in the early industrial revolution. American life expectancy also increased about 20 years or so in the years leading up to the 1920s.