Who are you, Wile E. Coyote? Just because something hasn't worked "so far" doesn't mean it needs to be abandoned. There are a shit ton of problems in our world and with our political system right now. But that's the historical norm. Even in the "good times" it's the historical norm.
Today there are so many people who have this weird belief that somehow the lack of change due to their extreme apathy is a justification for that apathy. It's not. If more people spent the time to educate themselves deeply on issues and candidates. If more people spent the effort to have legitimately worthwhile political discussions instead of merely agreeing with those who already agree with them and shouting down those who don't. If more people decided to take the risk and enter politics. Things would be a whole lot different.
Today the biggest problem isn't entrenched power structures, or gobs of money in political campaigns, or the lack of good candidates. All of those are symptoms. The biggest problem is that the primary ways that people learn about and discuss political issues are horribly broken. Most major news media outlets are horrid, only a few steps away from outright tabloid journalism. People decry fox news all the time but CNN and even the New York Times are, on the whole, little better, just different flavored output from fundamentally the same machinery. And people don't tend to realize this because every once in a while there will be something of legitimate quality that leaks through, and that event will serve as a rationalization for continuing to feed from those sources of information. These are precisely the same processes that keep people attached to religious institutions as well.
Ask yourself, how much effort do you, personally, put into researching political issues and candidates? What about your friends? Do you hold them to account for being low information voters? Do you ever have serious, non-shouting, political discussions with people who have different views than your own?