To some extent the miner is the vanguard of your ability to discuss this on the internet. We can't run the grid on lumber or "energy crops," and all the other options (solar, wind, fracking, hydroelectric, geothermal) have very similar environmental impacts to coal energy.
There's an advanced energy ecosystem that keeps a lot of really subtle and important things running as the human ecosystem evolves. Maybe at some point coal mining does get phased out in favor of less energy and cleaner energy, but you're gambling on that miner's tonnage not being necessary to clear that gap.
A society could also say, "No, coal stops tomorrow," but a lot of places tried "Everyone's a farmer tomorrow" in the 20th century for very similar reasons and hundreds of millions of people starved to death.
That coal miner isn't only feeding his family, that miner feeds and warms probably thousands of people. To phase out his job, you need a willful change in the infrastructure of the places he serves: you would need everyone to live somewhere without heating, to give up some amount of electricity use, and to begin food production independent of energy (which is a lark, if you've ever tried to grow a crop it is not easy, especially without Haber process or crop defense agents).