The significant enduring problem is that people are required to establish a right that they say they have. They are required to establish that at short notice, perhaps when they are simply accessing a health service to which they are entitled. The Government have not shifted the onus of proof on those people, so the problem continues.
Furthermore, because of the expanding of immigration control to those who are not qualified to exercise it, such as healthcare professionals and the police, people are not able to determine whether the documents that people present are adequate. There are many examples of that: people holding indefinite leave to remain stamps in an expired passport encounter the difficulty that the passport has expired, therefore the perception is that the Home Office stamp in it has expired, notwithstanding that it explicitly states that it is settled.
People who came into the United Kingdom on other schemes, such as so-called east African Asians who came without passports because they had no citizenship, find it very difficult to establish an entitlement in the UK. They particularly encounter that difficulty when they access something else; they are on the receiving end of Government action when they are not expecting it, and they do not have legal aid. Those are continuing problems that permeate many cities in the United Kingdom and have not been addressed.