You are saying overconsumption by the super rich is ultimately environmentally damaging. (which i don't disagree with)
I am saying underconsumption by the middle/lowerclass is immediately economically damaging.
Prioritizing investment over consumption leads to inequality and poor economic outcomes.
Curbing consumption is immediately damaging to the economy. The better solution would be to heavily tax unsustainable business practices, rather than try to curb consumption. If you go after consumption you give more power to the super rich, while simultaneously doing nothing to discourage environmentally unsound business practices.
Why is it better to continue producing products in an environmentally unfriendly way with lower consumption of goods, rather than lowering the production of environmentally damaging products, while raising consumption rates of sustainable products?
Go after the supply not the demand.