Because photo ID in the UK requires people to spend money, whether it’s a driving licence or a passport for example. There are a significant number of people who have neither, mainly because they are too poor. The poor, of course, are not generally tory voters!!
I mentioned in the ‘Votes for Expats’ thread that the ‘no taxation without representation’ view was coined in the American revolution and referred to votes for property-owning white men - there was never a question of. say, slaves or women voting. @JaneJones responded that the murky origin of a slogan doesn’t necessarily mean it’s wrong. She’s right, of course - there is no logically necessary link - but in this case there are very clear historical linkages.
Enlightenment philosophers like Locke are still frequently quoted as authorities by both rightist and centrist believers in ‘liberal democracy’ with little awareness that those ‘founding fathers’ did not believe in voting for everybody - they divided humanity into proper citizens and others, and founded a tradition that has a continuous history in politics - easily traced if you look at contemporary discussions of voting rights from the 1832 Great Reform Act, through to the 1960s civil rights movement - down to current Tory and Republican ‘gerrymandering’.