Water
Where water is more needed the underground water systems could be better worked with sea water filtration in stages like a power grid but a water grid working with the natural landscape.This could also be used to make water supply more ethical and ecological.

Food
This could be grown a lot in AI engineered vertical farms enough for good food for the entire planet. Meat could all be a bit more expensive and free range and vegetarian alternatives could be more tasty and better protean ect profiles.

Sewerage
Every thing that goes into the sewer could be bio degradable and suitable for storing as Pete. A lot Less tress could be chopped and killed in the making of toilet paper.

Waste
You only want 2 categories recyclable and bio degradable and you don't want to use the plastic range. We could by now have fibres for clothes paper and wood substitutes that can be recycled over 100 times.
everything in a car could be built of nano particles recyclable objects and these fibres.
electronic devices can be made completely of re-bondable nano particles and work at a photonic level so be very power efficient.
There would be no general waste bin.

Power
Tiles on roofs with panel and batteries will be a big thing also home batteries assisting the grid supply and demand will be popular.
Capacitive fibre networks can manage the global flow of electricity.
everything can be smarter and more economically tuned with the grid being ecologically sensitive.
True Graphene laced wiring should bring the amount of copper needed down globally.

Home living
cement ect free modular housing that is completely recyclable making use of the best materials but each part can be sold on or recycled. macro particle Velcro stones as building materials might help.
The whole building could be ugradable and adapted better to the environment and quality living conditions.
Compact villages could be build this way accommodating plenty with one road below for the whole village.

Space
The double wheel energy concentrator would be the way not rockets.

Transport
More automated/public transport options need to come on line and we need to deal better when there isn't a road connected directly to the home. Even boats and planes can be made of Recyclable nano particles and can be electric. ect

Clothing, paper and furniture
In the furniture could be Velcro macro sponges which could be repurposed.

Ecology and human welfare
A lot more responsibility could be put in the hands of the people via a government backed welfare savings currency giving more control over tax responsibility and a wider dynamic of support for people and the general ecology with things like more space set aside as commons and more people participating in the welfare of the world.
a life for a life policy carrot based not stick based global policy for human life might help balance the population.

If I woke up in that world 30 years from now and came down from my flat to outside I'll bet I get a good breath of fresh air and am more mentally stable and I'll bet prices would be efficient as sustainability is actually more cost effective done right.

What would be the carbon footprint of such a world. How much pollution would be dropped , how much of the landscape could be repaired how good would the products be and at what cost both financially and ecologically compared to not really doing much about sustainability. I think sustainability done right is cheaper and better everywhere that counts in the long run.