A surgeon certainly earns their salary, but one could argue that a hedge fund manager takes huge risks with their investment decisions that could literally make them rich or poor overnight.

Then for the inheritance comment I've never been able to understand how it makes sense to tax someone for money that was earned and taxed under someone else's name. So if my dad was a surgeon, saved all of his money and then dies in a car accident, I should be taxed for receiving his inheritance simply because I didn't earn it myself? I mean, the money is already subject to taxes on earned interest so it's not like the government isn't getting anything from it...

The Estate Tax was created to keep rich people from getting too rich. Literally. That's pretty much the exact definition of "government overreach."