[pm215]

Public transport within London has always been both differently managed/funded and also massively better than public transport anywhere else. If you're using London as your only data point you get a very skewed view of the UK public transport situation.

In this case, Transport for London (a public body) has always had much more control over public transport, specifically local political control, and has had the funding and long term planning horizon to set up things like the oyster and contactless payment systems. (And there are also practicalities, like the worst cases fare within the oyster zone being not very large, so it's OK to not take payment immediately but only when the system finds out where you got off, because you're not potentially out hundreds of pounds for a London to Edinburgh fare if it turns out the card being used declines the payment.)