Again, it comes down to new versus century old methods. More investments are going to go into developing new technology than improving old ones, because of diminishing returns on investment (there comes a point where improvements to a given thing are outweighed by the resources needed to realize those improvements). This Bloomberg article puts it succinctly, too — solar, wind, etc are technologies not fuels. This means that prices will continue to fall, and renewables will no longer need subsidies at all in order to be competitive with coal (and many sources argue that wind and/or solar are already there).
It also means that a lot of the subsidies for these early-stage technologies are intended to bridge the chasm of the technology adoption lifecycle and reduce the time required to get them to the point where these technologies can run under their own financial power, while allowing them to be viable on the market.
This is done largely as a long-game measure. As long as we’re using fuels instead of technologies, we’ll still be subject to the finite nature of the resources. We will eventually run out of coal, oil, and natural gas, and we need something to replace it. Given the length of time required to adopt new energy sources at more than the smallest of scales, now is the time to invest in those different sources to find the best one(s), while we still have the fossil fuels to fall back on. This is actually arguably a good thing for these industries as a whole (at least from a financial and longevity standpoint), because it increases the amount of time that they can be a part of the market, allowing them more time to research and improve, themselves. The extra competition, as well, spurs the coal industry to improve, instead of stagnating.
Also, regarding gas — if you read the article again (and read past the headline), you’ll find the author doesn’t actually argue against gas when it comes to prices, and in fact, specifically calls out gas as one of the nails in coal’s coffin. While gas certainly should have been included in the headline, to champion gas while saying the author is being disingenuous is…kind of ironic.