I think they’re lashing out. Coal is very harmful to the environment and to other people. They should pick a less violent hobby.
I’m just gonna assume you are making a bad joke rather than saying the couple hundred functioning steam locomotives have anything more than a negligible impact on the environment
Coal is going to stick around for certain applications for pretty much forever. What’d be interesting to see is charcoal refined to anthracite-levels of performance so applications needing that kind of grade can become carbon-neutral.
And it’s not even always railway enthusiasts operating the remaining steam locomotives btw in Poland they’re still in regular service. They phased out steam very late because of various economic reasons and once they did steam was already a nostalgic thing so they kept a depot and associated lines open. Contrast e.g. Germany where you don’t see steam in regular service but on various isolated narrow gauge sections.
There are very practical reasons for heritage rail to convert to oil burning rather than coal, including less abrasive grit flung all over the exposed running gear to not throwing burning embers all over the nation.
The grit isn’t much of a factor considering running gear gets dirt up in it anyways but there are plenty of railroads who convert their locomotives to oil over logistics and fire issues yeah
But in areas where coal is available and wildfires aren’t so easy to start can you really blame the museums for keeping their artifacts historically accurate?