100 companies are responsible for 71% of emissions. Projects that you have listed are important but more likely only help individuals to feel that something is being fixed instead of any real impact.
"100 companies are responsible for 71% of emissions" is referring to the fossil fuel energy companies. They're responsible for it in the sense that they pulled the carbon out of the ground.
That doesn't mean that if you buy an electric car or replace your oil furnace with electric heat pumps there is no difference being made. They sold it but somebody bought it.
Lets do the math. We will assume that 100% individuals switched to electric cars and heat.
Commercial and Residential Sector Emissions for US - 12%
All Transportation for US - 29% (It includes rail and aircraft. Only 60% of it is light duty vehicle and I couldnt find what percentage of it is commercial transport)
So we have 12%+ 29%0,6 = 32%. It is big number but now we have to produce same amount of energy in electricity. 79% of all electricity generation was fossil fuels.
32% (0.21) = 7%
So even if all individuals will stop using fossil fuels for heat and will use electric cars for transportation. We will have less than 10% of reduction.
Moreover, most of the fossil fuel generation is natural gas, which emits less carbon per unit energy than gasoline and large scale generation is significantly more thermodynamically efficient than small gasoline engines. And heat pumps are significantly more thermodynamically efficient than oil furnaces.
Meanwhile power generation from non-carbon sources is growing at a fast pace while coal is dying out, so that number will only improve over the lifetime of the vehicle/heat pumps, and if you want to get ahead of the curve you can install some solar panels on your roof.
