Customers don't have enough information to make an informed decision. I don't mind paying twice as much for something that will last a lot longer, but without a lot of research the price signal is the only indication of quality and more often than not it's just a premium for a well known brand rather than actual quality.

Indeed, that is the justification for planned obsolescence, the environment be damned.

Doing things that are unprofitable is also unsustainable on a large scale. It an only be done by using subsidies, i.e., other resources generated from profits, which does not scale.

Losing money is not a viable long term solution for a business, an economy, or mankind.

Accepting lower profit != accepting negative net profit and is far more sustainable for mankind than dogmatically seeking maximum profits.