If you want to make that argument, you'd at least need to look at the proportion of the population that's Western European, not just British.
The page I linked shows 53,8% white in 2021. Even if you count the majority of whites as West Europeans (and not East Europeans), they were under 50% in 2021, probably even less today.
If you have more accurate and up to date data, please share.
But that misses the point. I don't say London is not high-trust because of the non-Western population. I say London is not a western city anymore because of its population.
London has been a city of traders and other foreigners since at least the days of the Romans.
The dominant culture of the local population is not "Western" anymore.
> London has been a city of traders and other foreigners since at least the days of the Romans.
Is it?
Let's look at the official data: https://en.wikipedia.org/wiki/Demographics_of_London
Percentage of white population in London over the years:
- 1961 - 97,7%
- 1966 - 95,5%
- 1971 - 92,6%
- 1981 - 86,6%
- 1991 - 79,8%
- 2001 - 71,15%
- 2011 - 59,79%
- 2021 - 53,8%
It's clear that, up until very recently, London was a city of traders and other foreigners living there among the highly homogenous local population.