[inopinatus]

That deserves a challenge. Many significant contributors to US GDP are long-standing (>100yo) firms. Ford (founded 1903), General Motors (1908), Walgreens (1901), McKesson (1833), IBM (1911), Kroger (1883), Boeing (1917), Wells Fargo (1852), General Electric (1890), Johnson & Johnson (1886), Phillips Petroleum (1917).

Or the large companies that are repackaged versions of much older companies, with lineage back to the 19th century. Exxon & Chevron, for example, trace back to Standard Oil (1870); AT&T and Verizon (from Bell, 1877), Dow/DuPont (1897 or 1802, take your pick), Citigroup (from Citicorp, 1812). Banking often goes further back: BofA (Massachusetts Bank, 1784), JPMorgan (Manhattan Company, 1799).

Moving cuts of the pie around is a shell game. For sure the US is less regulated than Europe, so labels change more often, but the old money doesn't.

[Aunche]

17.5% of the S&P 500 is Apple, Amazon, Facebook, Microsoft, and Google. What percentage of the top European companies are that new?

[inopinatus]

New? Microsoft was founded 45 years ago, Apple is 44.

Top? The S&P 500 is riddled with mediocrities and rent-seekers.

17.5%? Five out of five hundred is 1%.

[Aunche]

Microsoft and Apple are still new by European standards. The only newish European megacorp is SAP, which is older than Microsoft and Apple.

17.5% of the market share.

[inopinatus]

Not sure what that number means to you, but see above about why it’s so low; established money protects itself.