[benj111]

"The win gap was at least 4%"

That's a narrow gap. Demographics (Brexit voters tend to be older) could easily have eroded that lead by itself in the past 3 years.

"Further, the native population was far higher pro Brexit"

The native population tends to have a lower birth rate also eroding the lead. Plus what is your point here? I cant think of a reasonable reason for even bringing it up.