I agree, but for more basic reasons than the creation of value.

On an economic level, sure, capitalism valorizes wealth creation. More importantly, though, capitalism doesn't prevent wealth creation. Degrowth means choosing not to use up some of the Earth's resources to create wealth. It means using fewer resources than we otherwise would. And under capitalism, if "we" don't use the resources, someone else will, because they can make money off it and nobody's stopping them. Degrowth isn't possible under capitalism, because under capitalism there's no way to stop people from using every available resource to maximize profit and therefore increase growth.

On a personal level, which is even more important, fear is the core of capitalism. People under capitalism learn everyone is selfish. Everyone tries to maximize their own profit at the expense of everyone else. Capitalism says you have to secure and protect the resources you need to live because no one will help you and other people will take whatever they can from you. So accumulating resources under capitalism is not merely greed - it's the only way to protect yourself after you lose the ability to accumulate resources from sickness and unemployment and old age.

So anyone whose worldview is based on capitalism will hear degrowth = I will have fewer resources = my family and I will be less safe. And that's the kind of barrier only re-education over generations can fix.