Grew up in a union family where I benefited greatly from the protections provided. But it seems to me that they really only help blue collar workers get higher, some would say reasonable, wages. As someone who worked their ass off for 10 years since graduating and negotiated my way to a senior role, I haven't seen one compelling reason to let someone negotiate on my behalf. Think of the smartest engineer you know. Are they in a union? Probably not.