1. Europe applies the same rules to Britons as it applies to all other non-EU nationals, just as the UK applies the same rules to Europeans as it applies to nationals of all other countries. There is a limit here on the length of stay for anyone who is not an EU citizen, just as there is a limit applied to British tourists visiting the USA, Canada, etc. The UK also has a limit on the length of time a foreign national can visit the UK, and this does not allow the taking up of residency. The termination of free (and extended) travel between the UK and the EU is the result of the British decision to break from the EU, not from any EU decision.
2. Only in the UK does one talk about “the Brussels rules” – on the Continent we call these “the British rules” since many of them were implemented at the insistence of the UK, or in order to make special arrangements in favour of the UK at the expense of the other EU countries.
We can only hope that Brussels will now eventually remove all these “British rules” to make our lives here less complicated. By the way, the phrase “Brussels rules” was one of the lies put forward by Boris Johnson when he was a reporter and before he was a politician, and he has continued this mis-statement ever since.
3. Britain never joined the Schengen convention, and one always needed to show proof of citizenship or a passport going in and out of the UK, even when the UK was part of the European Union. This has not changed.
Ron B. Thomson, Lagoa