Status Updates From Manifesto del Partito Comun...

They should use this introduction for undergrad history students as a lesson in how suggestive phrasing and jumping to conclusions can spoil an otherwise sensible base of research

Mid 19-century German socialists functioned as contemporary economic centrists, Marx says.

He further that said socialists loved to philosophize about “the general human aspects of society” and other such vague, philosophical, intentionally not grounded concepts.

So basically, Marx doesn’t like centrists because they’re functionally conservatives in saying “everyone’s good!“ Including the bourgeois.