Whilst it is the high profile environmental improvement stories , like heat pumps and electric cars, that hit the headlines in fact we could significantly reduce our hydrocarbon consumption with more conventional changes.
In the home there are many relatively inefficient gas boilers in use. If we replaced every unit that is more than ten years old with a modern far more efficient condensing boiler that would have a significant effect. Similarly the installation of double glazing and better loft insulation would be hugely beneficial. Better heating system controls and thermostatic radiator valves could also help. These are all relatively low cost and straightforward changes and government subsidies could be used selectively to make them available to all.

Home appliances are also far more efficient today and the replacement of old cooking, laundry and cleaning devices with higher tech modern ones would be beneficial.
Modern conventional vehicles are also far more efficient than those of only five years ago, let alone the many that are older than that. Replacing and scrapping a ten year old petrol-engined car with a modern more fuel efficient one would be easy to do and if people were incentivised to do this with grants the take up would surely be considerable.

Lifestyle can be moulded without too much intrusion if it is done thoughtfully. To switch travellers from the roads to public transportation is hugely environmentally positive but to do this you do need to improve services, introduce new ones and make them affordable. Critics of the High Speed Train HS2 should remember that every journey made on it will be far more environmentally friendly than the alternative of travel by car.
Long term strategies to increase the numbers of electric vehicles and heat pumps in homes (etc.) grab the headlines and can make sense. But there is still plenty of low hanging fruit to be picked that can be achieved in a far shorter timescale and lower cost.