Because the rich do a LOT to make it turn out that way.

• News is largely controlled by capitalists.

• Education has been gutted in a lot of places to make way for private schools.

• Corporations can contribute tons of money to candidates. Setting aside the possibility that these are effectively bribes, even if that weren't the case, the candidates who get that money get to put out more ads and have more campaign infrastructure such as travel funds, staffers, etc.

• Various kinds of voter suppression.

• From the very founding of the country, the election system and government has been set up to hamper political participation. Obviously there was the fairly narrow franchise at the start. But even with that expanded, we have the electoral college, unequal apportionment, gerrymandering, first past the post, closed primaries, a court that's specifically there to slow down popular will, etc.

• Just being a representative "democracy" puts a barrier between people and the policies they want. You rarely if ever get to vote on policies. You have to vote for a candidate. And the candidate is a whole bundle of policies, but also a record, a personality, etc. So there can be all sorts of political messaging about candidates which has nothing to do with what their policies are. Because of the duopoly party system that is all but ensured by the aforementioned voting system, you aren't even going to have a candidate you can vote for that will represent your interests. And after all that, even if you manage to vote for someone who says they'll do the things you want... then they get into office and you're back on the sidelines. They go and do whatever it was they actually wanted to do, and you have fairly limited recourse for holding them accountable. The most you can do is decide to vote against them next election, but now you're back to square one.

• Broader, more participatory forms of political organizing have been violently repressed. Just look at the history of union busting or the police violence during the civil rights movement or even now, etc. In the workplace, where you're most likely to find others who share your class interests, your boss has a lot of control over you and it's in their interest to make sure employees don't talk politics and view each other as competition rather than potential allies.

• Along similar lines, racism has been used as a tool to divide people who would otherwise share class interests so they wouldn't focus their attention on capitalists.

Moral of the story: There is a long history of people struggling against capitalists for a better life and an equally long history of capitalists using every trick in the book to keep them from that goal. The political landscape you see today is the result of that history. Learn from it.