"An international group of leading steel manufacturers today announced the formation of a coalition to urge the US and EU to adopt a global emission standard that incentivizes steelmakers to use the cleanest steel production process available." https://globalsteelclimatecouncil.org/
Global Steel Climate Council

The Global Steel Climate Council (GSCC) is an international coalition of steel producers and stakeholders committed to achieving a 1.5°C scenario by the year 2050 and establishing a global steel standard that leads toward a cleaner future.

Global Steel Climate Council
Renewing my prediction that "difficult to decarbonize" sectors are going to prove less difficult to decarbonize than commonly anticipated.
@drvolts aviation will still be difficult though.
@Transportist @drvolts also agricultural machinery and small boats. In all cases bio/synfuels likely the most viable option.