I can't say that I've found the attitude of the companies in London or Amsterdam to be materially different from what was described. That doesn't mean that it is the whole of Europe, but I'm willing to doubt that it is an isolated cultural thing.
Given that we both have wildly differing experiences with London, I'm willing to grant that London might have unique and positive offers now (my experience is from at least 3-4 years ago) or that I have at the time completely missed the healthy companies.
I think social / cultural differences actually is not enough to differentiate European start-ups. If nothing else, there is a tremendous (deliberate?) effort to follow American standards of management and GTD. However, at the same time, Venture Capital and management overall seem to be a bit more risk averse in Europe than USA.
But thats just my opinion of what is the common denominator here in Europe.
I can't say I've had the same experience working for start ups in London, in fact I've had the opposite - competitive pay (probably about 20% less than working in tier 1/2 banks but above market in industry), good benefits (incl. private health, gym etc.), fair work life balance (incl. holiday days and WFH policies) and rewarding work with intelligent colleagues. Non-EU/UK workers that I've worked with have the same experience as far as I can tell (perhaps even more positive, considering that some of them require visa sponsorships).