I think the great problem with the SDG's is that they are development goals, not sustainability goals.
We should reverse the priority, to have top priority go to measurable progress toward hard targets for achieving sustainability. It's quite possible scientifically, but we’d need to use “The Commons Approach” organizationally (1). The tragedy now occurring, with the effort having the wrong order of priorities is that the implicit "sustainability goal" naturally becomes to make an effort to slow the rate of growing unsustainabiliy of the economy.
That is being achieved but fails as a way for the economies to become sustainable. It may well be thought of as an important step, but if we face the truth, it’s a total failure as a plan. You see that unfortunate trade-off in most agreements and metrics, a plan to slow the rate of growing impacts…. but it's a disaster for the earth and for the future of our complex societies.
1) The UN is Urged to Adopt “The Commons Approach” at All Levels Of Government and Throughout Society, to Achieve Real Sustainable Development and MDG goals