"one source" is a misrepresentation. Coal is burned in many regions of the planet. But each of these regions has different structural characteristics. It is not possible to solve one big "coal problem", because it is actually many individual energy supply problems that need to be solved.

Of course we need to do everything at once, that's how any change of this magnitude has to work.

I assure you the people who suggest flying should be limited to reduce carbon emissions are not the same people "kicking the can down the road" for half a century.