Anecdotally it is much, much, much easier to get a $400k tech job in the US than a $300k tech job in the UK, so this isn't really a fair comparison
when I moved from a tech job in the UK to a tech job in the US, my salary more than doubled
when I moved from a tech job in the UK to a tech job in the US, my salary more than doubled
And I'd still take it over the US.