"One of the rights we've grown used to in the UK is not being challenged for our "papers". "
Takes a bit of cheek to post a comment like this to an article about people facing deportation because they have literally been challenged for papers, and those papers were shredded by the same government agency demanding them.
The reality of life in the UK is that you are constantly challenged for papers in order to do anything from opening a bank account to renting a flat. Therefore you either need government-issued ID like a passport or else you are at the mercy of whatever the deranged bureaucrat feels like asking for.
"On a practical basis how does such a paper-based registration system get booted?"
Since several european countries have successfully operated such systems for decades it's clearly not impossible outside the constraints of Little England.
"Does every baby get micro-chipped at birth so that in 70-80 years we have completely documented population?"
And yet more drivel showing that you completely fail to grasp the distinction between recording someones details and proving their identity. Sadly this is absolutely typical of people raised in a country where the authorities are unable to achieve either task.