No, it isn't. There is no law against worker co-operatives, so it's not a question about "economic model." Not a question of "political economy," just about one particular form of organisation and a no-issue.

I do not think there was any law against paying your workers in Rome, yet slave labor ruled, proving its superiority over wage labor. There was probably no law against corporations in medieval Europe, proving the superiority of the feudal system. So yes, it is at its core a conservative argument.

That something is legal is only a subset of the conditions necessary for an organisational form to thrive. Just to pick an example I am familiar with: in 1931 it was not illegal to form a co-operative bank in Denmark, but in 1933 it became illegal.
JAK members bank - Wikipedia, the free encyclopedia

The co-operative society Jord Arbejde Kapital was founded in Denmark during the Great Depression in 1931. The society issued a popular local currency which was subsequently outlawed by the Danish government in 1933. In 1934 it founded an interest-free savings and loan system and a Local Exchange Trading System. Though both systems were forced to close, the savings and loan system reemerged in 1944.

Economy is politics with other means.

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