Capitalists argue this because it gives them the appearance of a moral high ground.
Eshittification shows how untrue this - capitalism by its very nature will always devolve into worse and worse offerings because it's reliant on squeezing out ever more profit.
Capitalism will only ever puh out the bare minimum of technological advancement. And keeping people in indentured labour (aka employees) to the capitalist system so that they either have no time to come up with innovations themselves or they own the intellectual property of any indentured workers means that the overwhelming majority of innovation is monopolised by capitalism too. Which also contributes to the appearance of pushing advancement.