"Mum was 21 in 1960 and so they lived through the 'swinging' 60s with peace, love and flower power. They had friends and colleagues from all races and religions."
In that case, your mum was likely a very unusual person.
At the time of the 1961 Census, the population of England & Wales was 46,104,548.
Of those, 192,031 (0.42%) were from India, Pakistan or Ceylon (nowadays Sri Lanka). A further 171,293 (0.37%) from the British Caribbean Territories. There were also 35,461 (0.08%) from British African Territories.
In addition to this there were 179,338 (0.45%) from other Commonwealth areas and 722,160 (1.6%) from foreign countries and 762,203 (1.7%) from Ireland.
Now, I wouldn't exactly count the Irish as foreigners (although they technically are) so, leaving them out, in 1961 there were around 1,300,283 (2.8%) people living in the UK who were born in a different country.
Or, to put it another way, 97.2% of the population were white British.
That your mum knew multiple people of different ethnicities suggests that she was living in one of very few places in the UK where this could be true.
These places included Birmingham 38,260 (3.46%), Islington 29,074 (12.73%), Wandsworth (26,044) 7.5%, Willesdon 22,777 (13.32%), Lambeth 21,747 (9.72%), Paddington 21,329 (18.24%), Hackney 19,840 (12.04%), Manchester 19,730 (2.98%), Hendon 17,830 (11.74%), Bradford 14,872 (5.03%), Leeds 14,013 (2.74%).
Outside of these few northern cities and parts of London, the UK in the 1960s was overwhelmingly white British (and even then, even Birmingham was 96.4% British and Bradford was 95% British)** .
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"I'm in my 60s and grew up in the 1980s under Thatcher where we (myself and my friends/cohort) were extremely politicised - we marched for miners, "
I'm very likely a very similar age to yourself. The first time I voted was in the 1983 general election and I voted Conservative. I've voted at every election since then, I do believe that it is important to vote.
I remember back then speaking to a couple of girls who were slightly older than me who had been at the Greenham Common Women's Peace Camp. We had quite a spirited debate and eventually agreed to disagree.
I'd just point out that just because a person disagrees with your politics or your point of view that does not mean that they are "racist, right wing bigots who vote Reform and hate 'foreigners' "
[EDIT]
Curiously, the areas with the absolute highest percentage of foreigners were Huntingdon, Mildenhall and Hunstanton. With around 25% of the population being born abroad.
Although, in these cases this was down to the local US air force bases which had thousands of US servicemen. Although, they were just here as expats rather than immigrants.