To me they're like mere servants of the State, like Lenin talked about in "2. What is to Replace the Smashed State Machine?" in his writing "The State and Revolution"
Under Capitalism, they are its privileged knights that try to deflect and control, if not defend directly its image as "the only option", who have their incentive in doing so, with their class status stake being in their duty to shepherd the means of production and its resulting benefits
However, they don't own the means of production, as they merely manage it for the landholding, industrialist, and financier capitalists
On the other hand, under Socialism, while its privileges will be probably be done away, the PM class on its own would innovated upon, for their new duty of overseeing, managing, and reporting the collectivized cooperatives and state-owned enterprises..
Until the final stage of Communism arrives, I think they're pretty handy
I say this, because I hear such disgusted sentiment in Hexbear against them
You can look to the history of previous successful socialist transitions to see how many of the mandarins of the capitalist class were repurposed under socialism. What else would you do with them, and how would things continue to work if you didn’t make use of their relatively unique working knowledge of things?
The PMC is usually considered a much larger group than just the “managers”: it includes the “professionals.” College professors, scientists, engineers, journalists, etc.
Edit to add: It’s not as if these people would have alternatives to socialism after private property is abolished, other than emigration.