UK's pay is extremely low. And you know that it is VERY difficult to earn beyond £80k/yr as a SWE outside of top foreign employers in the UK like Google or Citadel. More likely, you'll stagnate at £50-60k.

And when factoring the UK's CoL being comparable to some of the more expensive American cities (SF, NYC, Boston) yet salaries being a fraction of those available there, it makes sense why engineering isn't well regarded, and plenty of people either switch to finance or immigrates to the States, Australia, or Canada.