Ya know this election could end up as:
Money talks (Bloomberg and his ads, etc)
Bullshit walks (Trump, no explanation needed)
But the truth sticks around, (Bernie with the same self consistent message for decades)
America has many problems that stem from the decades of pernicious lobbying and outright bribery that warped the tax code and policy favoring the rich prevalent in any capitalist society. Bernie might help to reset the game and level the playing field, perhaps hedge fund mangers will pay a reasonable tax rate and that the biggest most profitable American companies will pay some instead of none.
The combination of capitalism, technology, mass markets and trade has lead to rapid material progress, but at certain costs, both social and economic, one of those issues is the concentration of wealth into a few hands with social and economic consequences for the vast majority. This phenomena has been going on for a long time and when the railroads (and steel etc) became a major industry in the 19th century it produced the robber barons and the concentration of wealth of the gilded age, you need another kind of Teddy Roosevelt this time around. The internet is kinda doing what the railroads did in this regard today only on steroids and allowing the concentration of vast wealth into few hands.
An economy is an ecosystem and the little fish and plankton have to thrive for the big fish and whales to flourish, a balance must be struck and that's the job of policy. When policy is bought and paid for it distorts the playing field, the rich have built in advantages where they should not. Bernie's message is really and always has been an anti corruption message more than a socialist one, he is not against capitalism, he just doesn't want it to own the government.