Also this is only talking about trading at bulge bracket banks like UBS but "Wall Street" is much larger and more complex than that.
As for the stress and greener pastures bit, really you aren't wrong.
Two friends at Apple illustrate: one says he does basically nothing but surf the web, the other last I heard is is nearly sleeping under his desk in a crunch.
Banks are where the arbitrary high stress jobs reside, and then certain specific companies that choose to enforce stress culture, like GSAM and Citadel.
But most have normal 9-5 hours, few deadlines, autonomy, project self-selection.
Not much different than shipping something broken to millions of users and needing to triage a rollback.
Of course there are outlier firms that play fast and loose and can have risk of huge sudden losses that can’t be stemmed, but most firms do risk management as a core part of their purpose for existing, and this applies to risk of bad code / bad model just like anything else.
Again, maybe I just don't know enough about how it works, or maybe I just know enough about what I do -- but every once in a while you make some catastrophic mistake that takes done Google or Facebook for a few minutes -- the only cost you incur is opportunity. The same mistake at Knight Capital cost them like $500M in 15 minutes or something crazy.
So, taken a step further, the little bugs that regularly make it into Google that cause 1% of requests to 500 on some service is a big deal, the opportunity cost can exceed your salary for years. I imagine the same thing is true in trading, except it's not opportunity -- it's real money. That just seems way more stressful to me, but maybe it just doesn't happen very often, or the test coverage is taken much more seriously, and it's better.
Don't know about London though. All values in USD.
Even when buying individual equities I would get emails indicating my trades were flagged for further analysis. It isn't enjoyable to be good at managing money but unable to do so without fear of punishment.
Even though I follow the rules, the process made it too difficult to manage. It is a real opportunity cost because in order to invest aggressively I would have to quit.