That might be the case in the US where capitalists have much more influence over election outcomes and politicians themselves are often part of dynasties that accumulated enormous wealth. This is however not comparable to many European countries. Sure, you have capitalists in all capitalist societies. But their direct influence on election results is much smaller and politicians are very often ordinary people and not obscenely rich or privileged by their ancestry.
A whole different aspect is that these ordinary people, once they came into power, lend their ears way too much to capitalist interests and the likes of lobbyists, often ignoring the problems and needs of ordinary people and focussing instead on catering to the industry.
The people could however not vote for these politicians if they realized that their policies thwart their own interests. If they fail to do so, it’s their own fault that the conditions for the majority are not improving. How can you fix the stupidity?