Speaking as a Brit, though, it is not generally the Londoners who are complaining about the immigration.
It is the rural counties, who get the least of it. Speaking from experience, as someone living in a county that is (as per the 2021 census) counted as 95.2% White British, and yet has a strong Reform showing, and having to deal with countless friends and relatives complaining about “the immigrants”. The ones that simply don’t exist here.
It helps put into proper context that Reform’s popularity in many places is more cultural than demographic - based on feelings more than facts.
You can argue that immigration is a legitimate problem, but you should also have an answer to give in regards to people like the ones in my local area, whose view of immigration isn’t representative of any sort of lived reality, but is completely manufactured. People like the ones in my locality rightly delegitimise concerns about immigration for many people, because it shows how people can irrationally fear it without any experience of it at all. It shows how concern is often an issue of false perceptions, rather than being grounded in reality.
Where I am in the UK, our driving lessons involve keeping an eye on the speedometer, so that we’re not constantly going over. Many modern cars also have digital map functionality built in (or you could get a separate device like a TomTom), which will often inform you of the speed limit between areas.
8mph difference is only possible to accidentally go over until you are taught to be hypervigilant about your exact speed and start having your eyes on the speedometer as much as the road, and then you start realising rather quickly when you start going over by even 2mph and correct it.
Lots of cars ignore it at their own peril, choosing instead to be hypervigilant for the speed cameras. My own father (a stresshead in the car) regularly speeds around, hoping not to get tickets. My point is, though, that it’s not difficult to be taught to control speed if people choose to want to.