Good folk are thinking about this, but something incredibly relevant that makes a huge difference is being consistently ignored, by both sides in the growth / degrowth camps, it seems to me.
The book you mentioned written in 1972 was before the advent of solar energy.
It never was true that the Earth stands still, though the capitalist economy demands that it does, nature when it is healthy is creating all the time, adding value to Earth in the form of new life.
Imagine, what would happen to the value of a piece of gold, if nature found a way to start growing gold on trees, suddenly all the gold being kept as capital would devalue, because anyone could get some just by picking it from trees.
You can bet that at first, all the humans holding gold would be screaming "No! It isn't real gold growing there, because that gold is growing for free, our gold, that we sacrificed everything for, is still the only real gold, come and give us your labor, to have our gold!"
But this is in effect what is happening to oil / fossil fuels; something functionally replacing it with none of the pollution, therefore even more valuable than fossil fuels, is being created for free, by something we might recognise as a human version of trees, at an exponentially increasing rate around the world.
Notice fuels are treated in the capitalist economy as commodities; a fixed value is put on them, even before they are even dug from the ground, forecasting an amount of effort needed to do the digging.
So money is issued on the expectation this digging will have to be done.
But as the newly arrived fuel growing on human trees for free, continues to become more prevalent, that money issued is losing value.
Hence we see inflation, inflation like no other seen in history.
This time, instead of creation of product trailing issue of money, it is issue of money trailing issue of product.
That means the effect of issuing more money is the opposite of what used to happen, before the new fuel product started to be created.
The previously painful cure for inflation, of issuing less money rather than more, to those badly needing it, doesn't work any longer.
Now more money has to be issued, to try to combat inflation.
Of course like the gold holders, the money issuers are desperately trying to claim we still need their precious money, but they are struggling to keep pace with tokens which are issued on work already done by the new fuel.
The new fuel is hydrogen, but this is only one form of the new economic product coming from solar energy.
In the end it charges cars, heats and cools homes, even powers industrial processes, and all the servers on the internet.
All of it is economic product, and since it started coming from solar, it can no longer be classed as something constant, but actually a function of time.
Notice that a constant, any constant, , in presence of any increasing function of time becomes valueless relative to the time dependent term.
This is the mathematical proof of the technical end of capitalism.
The fact is that by not issuing UBI now, a substantial UBI, reflecting what is being added to the economy for free, from solar, this is the real, physical reason for inflation, which will not stop until the money representing the outstanding and ongoing, exponentially increasing, unmonetised solar product is honestly and authentically reflected by issue of money.
The days of unfair distribution of wealth are coming to an end, forced by nature.
Degrowthers seem to not like this much, because issue of the money needed as solar backed UBI will result again in growth.
But they haven't noticed this growth, fueled by solar energy, is the opposite kind of growth as we saw previously, fueled from energies of Earth.
That previous growth of ours occurred by destruction.
The net effect on Joules usefully put to work by us throughout our previous growth was reduction, of things created by nature.
Whilst nature was busy creating, we were busy destroying, creating pollution permeating our entire environment, with the effects we are seeing now as climate disaster, viruses, and even wars.
That destruction is the thing unsustainable.
We've been busy destroying, whilst thinking we were creating, this was what we called "progress".
The price for it was paid by all the victims of of colonialism, and the victims of the environmental pollution, all put together.
We can say nature forced this on us, we never had a choice.
But now we have a choice.
We can choose to be born as a species from dependence on the finite energy of our mother host or not.
The choice nature is giving us is the same as it always was.
Do it or die, as a species.
Living, will involve growing like a plant that just formed it's first leaves grows.
It grows to many times it's size as an infant, but instead of being a subtractive load to its mother host, it changes from the point it forms leaves, to become something adding to it's mother host.
This will be us moving from destruction, to creation.
It starts, on formal issue of solar stimulus, that is a solar backed UBI.
Until then, we are just dying.