UN agencies will describe sustainable development as a state of nirvana where social justice, equity, and environmental balance prevail.
Climate change experts would want the world to achieve net-zero emissions today and not by 2050.
Companies look at sustainable development where costs, revenues, organization systems, and processes are in harmony and a company continues to grow steadily.
If you look at the above three states, we will note that they all describe an ideal end state. It is a state we are unlikely to achieve in the real world.
Sustainable development goals perceive significant value—concentrating on the needs of hindered groups, children, women, and the poorest of poor to attain sustainable development of human ambitions and to confirm a healthier life for all.
Sustainable development is an organizing principle for meeting human development goals while sustaining the ability of natural systems to provide the natural resources and ecosystem services on which the economy and society depend. The desired result is a state of society where living conditions and resources are used to meet human needs without undermining the integrity and stability of the natural system. Sustainable development was defined in the 1987 Brundtland Report as “Development that meets the needs of the present generation without compromising the ability of future generations to meet their own needs.” As the concept of sustainable development developed, it shifted its focus toward economic development, social development, and environmental protection for future generations. (Wikipedia)
I regard sustainable development as more of a philosophical concept in which we live in a world where there are no poor; humans live in harmony with nature. It is a goal that we will continue to strive to achieve. It is a good goal; it makes us feel good about ourselves. It is a goal that we as a human society will continue to strive to meet. We must believe that we will meet these goals, or we will never give succor to the poor.