unless you consider Smith, Marx or Engles philosophers

uh yeah, very much so. and the fields of philosophy, math, physics, computer science continued to be deeply intertwined well into the 20th century. so I consider Godel and Church to be philosophers too. possibly Einstein, since most of the great debate in physics at the time were fundamentally philosophical debates. it's really infortunate that this strict separation and hyperspecializstion has become the norm nowadays. probably why physics hasn't produced any major discoveries / paradigm shifts in a century.

I learned about Z-F set theory and the logical foundations of mathematics in a philosophy class while I was pursuing a math degree, found it super helpful for later topics in math like advanced logic. the prof was one of the last members of the old guard, straddling the STEM-humanities divide. he had studied under one of the great polymath (interdisciplinary?) figures of the 20th century, and was himself an expert in a handful of fields that to me seemed unrelated. I would go on to be a huge nerd in many of these fields and learn the importance of breadth of knowledge.

even worse than engineers who think learning to read is below them is all the scientists who don't know the first thing about the philosophy of science.