The key problem is that, as the article highlights, iron is widely available and its energetic cost per ton is relatively small. This means that we actually need to reduce steel production, not just replace it with something else and call it a day. Doing the later would cause more harm than good.
For that, I think that consistent application of the three R's (reduce, reuse, recycle - in this order, and stop forgetting the first two R's dammit) would be a good start. And perhaps legislative measures against businesses trying to prevent you from applying the three R's.
In the meantime, perhaps look for alternative steel productiion processes? You need some carbon as it's part of the alloy, but I wonder if the bulk of the reduction could be done by electricity instead. And even the carbon could be sourced from renewable sources; more expensive, but doable.
The folks who came up with the 3 R's (plastics industry) knew that only the first one made any difference whatsoever.
Even today, plastics recycling only makes a trivial difference. Edit: And a lot of things saying "uses X% recycled plastic" are often referring to the plastic recycled in-house through the manufacturing process, which they've always done (such as flash from injection molding). Unless it says "post-consumer" it's just moral grandstanding.
However, steel is the most recycled material today, and glass is also good at being recycled. But glass has a weight (and therefore energy) penalty, which likely outweighs recycling benefits.
Electric arc furnaces are becoming more common across the steel industry, coke alternatives not so much. Being a commodity, any steel plant that chooses more expensive ingredients is going to quickly go out of business
any steel plant that choses more expensive ingredients is going to quickly go out of business
That's true, and perhaps governments could/should kick in. The shift would be overall advantageous for society, so I think that it could be viable to tax coke production and use those taxes to subsidise plants using greener energy, offsetting the costs.
In the meantime, perhaps some global measures. Such as a treaty specifically addressing steel-based carbon emissions. Big thing here would be to convince the big three (China, India, and Japan); if the shift is desirable and viable for those three, others are easier to convince.
Coal is a significant component in the production of steel to impregnate it with carbon. It's a fundamental part of how a blast furnace operates. The article literally talks about this...
Even the article about doesn't mention an alternative. An arc furnace relies on scrap it cannot make new steel.
Though, I wonder if we can move more towards charcoals, but even then I wonder if that's just much less effective or if it cannot reach the temperatures or concentrations required for industrial processes.
Coal is required for steel, electricty-based heat would only work to lower carbon emissions (especially when recycling steel since you don't need coal there), but you couldn't prevent them.
That's fundamentally different from steel. We don't really have an alternative currently. You could use something like aluminium but that's not environmentally friendly either (in the initial production, for recycling it's great).