That’s pure speculation on your part.
The only thing that chart shows is an extreme drop in coal tonnage shipped. It does NOT show that it was replaced by NG. Of course there was an increase in NG because of fracking, which is also on the ropes, but you can’t claim the reduction was singlehandedly replaced by NG.
Anyone/everyone knows the precipitous drop in US manufacturing which was replaced by Chinese manufacturing in the last 20 years results in less energy hauled by rail, truck and pipeline in the US.
Even if it WAS replaced by NG hauled by rail, what if that NG was being exported to countries like China for manufacturing? Then it proves my point even more. China has taken nearly all our industrial base away. That’s a huge concern.