The post office scan is now part of the proof of identity check , every time you apply for a visa in the UK you will be biometricaly checked
They have certainly become more thorough. They do it at the English test too, now, as well as taking a voice recording. Not a bad thing in my opinion. Immigration checks have been very slack in the past, I feel, and this should help stop fraud and cheating in the tests too. So there are some plusses to the new, stricter methods too I guess.
You're right Keith, other forms of identification and the like are required, if you're a Brit it is straight forward and you can just show your passport and NI card to a new employer as proof eligibility, Foreign Nationals have to prove they are entitled to stay and work in the UK (BRP is handy for that) along with passport. https://www.rcs.ac.uk/wp-content/uploads/2014/05/Applying-for-a-National-Insurance-Number.pdf