It’s a huge stretch to say the S&P 500 isn’t the current top 500 stocks by market cap just because they don’t include several recent IPOs and have discretion to exclude stocks based on potential stock manipulation. These are very rare cases that have little affect on the overall index. In time (not instantly) they add large established companies. Proportions are always weighted directly to market cap percentage. They’re not weighing some stocks higher than others like how an active manager would allocate.

Agree “beating the index” is quite a joke since that is the benchmark for fund performance and so much money is passive invested now. Matching the index performance is saying “our fund equities have appreciated on equal basis to how all others have”.