It’s market cap rather than revenue or employees. Exxon’s raw material (oil) was expensive, had high price volatility, didn’t scale, and required (relatively)

It’s market cap rather than revenue or employees. Exxon’s raw material (oil) was expensive, had high price volatility, didn’t scale, and required (relatively) more people. This capped gross margins, and made growth expensive. Facebook’s raw material (bits/electricity) is much cheaper and has Moore’s law at their back. It scales well, as does their (relatively) lower headcount. They get valued much higher relative to revenue or employees. This makes the market cap a weaker proxy for usefulness.