Let's face it, political parties are designed to divide the people. Why that ? Because political power like every power seeks its own limits. It looks to increase its own power. In a (so-called) democracy, government negociates the boundaries of its own power with the people. One way to get more power for the governement is to weaken the people by dividing them. Now you see the people divided in many different ways w…
This implies that government, in and of itself, is a conspiracy to perpetuate consolidation of power. That's enough of a broad generalization that I can't take it seriously - while it may be true for some forms of organization, I don't think we have enough data (or the right KIND of data) to actually make a call like that, let alone claim that political parties in particular are defined by power orchestration by a ce…
For instance, look at Duverger's Law (https://en.wikipedia.org/wiki/Duverger%27s_law), which says that the standard "one person one vote" voting system we use naturally tends to produce a two-party system. Beyond that, there are institutional tendencies towards compromise and centrism that will tend to make key parts of both parties similar to each other and drift towards each other, while roughly matching overall society sentiments, and emphasizing a handful of ideological differences that match/create those in society (with a feedback cycle). Put that together with standard political tactics like proposing an extreme position and "compromising" with what you wanted in the first place, and with the tendency of any system made up of people to perpetuate itself and give itself more power.
So it's entirely plausible that we'd naturally tend towards something like we have: a two-party system, with differences on some high-profile items that, common agreement between those parties on other issues (most notably on the self-perpetuation and growth of government and bureaucracy, even if in disagreement with substantial fractions of the public), near-impossibility of electing a third-party candidate, etc.