It is the worker owning the mean of production, so i don't think you can do more socialist than that to be honest, it's almost the definition of socialism (communism for fellow europeans).
You can find some differences between western co-op and the socialist ideal (mainly, you still have hierarchy and a power structure mostly determined by how much you make), but to me it seems mostly academics.
This is one of those cases where subtly different definitions of technical words are being used in contradictory ways. A very common definition for capitalism vs socialism in Leftist spaces is concerned with power and economics, with socialism being when labor has the power to dictate the allocation of capital, whereas capitalism is where capital has the power to dictate the allocation of labor.
A more political definition looking at government is "socialism is when capital is allocated for the benefit of the collective, capitalism is when individuals are granted exclusive ownership of capital to allocate how they choose".
Note that a worker's co-op meets the first definition of socialism, and the second definition of capitalism.
You can find some differences between western co-op and the socialist ideal (mainly, you still have hierarchy and a power structure mostly determined by how much you make), but to me it seems mostly academics.