The verification of ballot papers done at the Counting of the Votes begins with ensuring that the number of ballots given out matches the number taken out of the box.
The counterfoil numbers are kept seperate from the ballots and the use of them is usually one safeguard against photocopying ballots or using fake ones.
It would be theoretically possible to match ballot to voter were the papers not inside a sealed box for 14 hours, driven to a counting hall, and then combined with the contents of other boxes for counting. Their use is usually to ensure that the ballots were given out sequentially to avoid suspicion of missing or amended ballots.
Coercion can occur at a polling station. Staff are trained to check for people who might be standing too close to voters.
The recently passed Ballot Secrecy Act (
https://bills.parliament.uk/bills/3172 ) places further safeguards against coercion inside polling stations.
Many years ago now, Individual Registration was introduced to avoid the 'head of the household' issue regarding the filing in of the annual registration process. This was in response to concerns that it was possible for postal voting to be manipulated in the ways expressed with some vigor by one poster in this thread.
To return to the main requirement of this thread, the photo id rules have been introduced to solve an issue that doesn't exist, and requires younger voters to use ID they can't afford nor access. I'm certain that's the more pressing issue than whether a crypto-bro who uses "woke" as an insult should be any further indulged.