As a Swede in Switzerland, I think the main difference to the US is the cost. European commissions is mostly "buy and never look again." That fosters a culture where only a few people care and talk about it.
In Switzerland, I have to pay ~0.1% stamp duty on every purchase and sale of stocks and ETFs (in a Swiss broker). The UK has a 0.5% stamp duty on stocks. The idea for these brokers to compete on price doesn't make much sense at that point. It's "fine" that the normal fund has a 0.5-1% fee. There's some movement here, but only if you care to engage outside your existing bank (IBKR in the UK, Avanza++ in Scandinavia, Degiro in Europe in general).
Investing is good, and---as has been said---pensions are often invested in the stock market, whether you know it or not. But you just don't talk about it, because being active is costly. In Sweden, the defined contributions are auto-invested in a balanced fund unless you engage. There's something to be said about having sane defaults when you create a system.
As for the US, I'm not sure Robinhood was a step in the right direction. We should encourage people to own companies, not try to profit from Brownian motion. But that's perhaps a topic for another discussion.
Finally, I'm heavily into the stock market. I have several accounts across the world (though not really by design). I'm fascinated about this oddity that I can buy more food in the future just by having a different piece of paper, compared to someone else. But I also spend a stupid amount of time trying to find ways to reduce cost of investments. My guess is that most people don't, and it's kind-of the first step for a European that's paying >1% in fund fees. Or who don't even know how much they're paying.
