That’s just pedantic

Eh your teacher does not know what they’re talking about in the slightest.

Socialism does not have to be centrally planned. For example, you could have market socialism by just making every company a worker cooperative.

I find it so ironic that the comment above you is literally saying that being progressive means challenging what you [think you] know, but you are being downvoted by (I assume) people who call themselves progressive, without any discussion.

ITT: left = progressive and right = conservative