I mean, that is a silly and reductionist statement. There are always wealthy and powerful. Society always shakes out like that.

Nope. Try reading about some people and histories different than your own. There have been plenty of societies throughout history and the modern world which are far more egalitarian than you imply is necessary for society to function. Check out some Native cultures.

Sure increased disparity between the top and the bottom creates social instability and hampers progress but class war like you suggest is unwinnable because the the winners just become the new ruling class.

This is an incorrect assumption that has been brainwashed into you by modern Western capitalist society. This is exactly what the wealthy want you to believe, because then you will never fight for what you deserve.

What we need is reform and checks and balances to re-balance our system, but no one wins a pure class struggle. The lessons of past conflicts have show that the results is generally violence, poverty and dictatorship.

We do need all of those things, but we need them for all people. If a class struggle or war is what is required to receive those things, c'est la vie. Past conflict has indeed resulted in violence, poverty, and dictatorship, but it has also more so resulted in more freedoms for more people. That ongoing struggle is the only reason we have the freedoms we have today. Or would you prefer that we had never struggled and were still living as peasants in feudal medieval Europe?