If you follow your argument logically, it says there's nothing to do and we're in a good place.
You said we need to have 5.4tCO2/person/year on average across the world. You then presented a table that shows that we are in fact _under_ this target (4.7t). In your follow-up comment you claim that the lower-income countries are "never going to emit much more than they do now". So by your argument the world average will probably stay below the 5.4t goal and we're on target.