Check the top companies in Europe, it's mostly the same companies founded 100 years ago or something. The increased regulation in Europe just helped existing big companies, not new ones. Compare this with the US where the list changes every 20 years or so. https://www.forbes.com/sites/jonathanponciano/2019/05/15/eur...

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.

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

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%.

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.

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