The problem with machines (and such) as capital nowadays is that the machines are expendable soon because of fast technology progress and obsolesce turnover. The whole industry business model is based largely on planned obsolesce. Material resources get little respect as capital. Like in the "Monopoly" game, the purpose is to score that funny paper. The real capital with power is the capital of implicit promises and privileges represented by money.

The whole purpose of economy seems to be not to serve some needs of aggregate production or producers. Rather reversely, production exists to serve needs of financiers and rentiers. They have such a huge volume of implied promises and privileges, that they can hardly do anything with it but nominally grow or convert it to commanding social power. And the whole political-economic system is geared to satisfying that.