It's precisely because fixed costs are so high why the railroads are so intransigent, especially considering they've been captured by activist investors. High f

It's precisely because fixed costs are so high why the railroads are so intransigent, especially considering they've been captured by activist investors. High fixed costs raises the stakes for swings in variable costs. And labor accounts for ~40% of variable costs (circa 2009 per https://www.ndsu.edu/fileadmin/challeyinstitute/Research_Briefs/USDA_Report-Railroad_Rates.pdf https://www.ndsu.edu/fileadmin/challeyinstitute/Research_Bri...) (I can't find numbers for variable or fixed costs as percentage of total operating costs, but it seems fixed costs are definitely >50%, especially since deregulation.) The import is that the railroads will likely need to be forced to provide sick days. Both because management and investors are so sensitive to variable costs, but also because there's a collective action problem--any one railroad doing this immediately puts them at disadvantage to the others in terms of stock prices. But just as you say, any mandate is unlikely to result in significant real costs to customers. Alternatively, maybe a Musk-like industrialist could swoop in with ideas on how to reduce fixed costs, shifting emphasis. But that seems unlikely. The whole industry seems to be completely geared toward extracting as much value as possible without investing capital.