There are a lot of problems with career politicians. They tend to be from a very small set of occupational backgrounds. They are not representative in any way, from gender to race, of the actual perspectives or life circumstances of Americans.
But there is something to be said for expertise. Many of the people in Congress not only have worked on a real skill that has complexities but also have learned how to consult their young aides who have all sorts of different academic backgrounds. A lot of politicians are smarter than they may sometimes look, even if they still are often way out of their depth in the matters they're trying to craft policy for.