thread Yes the UK has been very secular for a long time
and I strongly suspect (although have no way to find out) that plenty of people who say they're Christian merely mean that they had RE lessons at school (which were basically only about Christianity when I was at school) and would get married in a church if they were forced to have a religious ceremony.

All the schools that I went to had a religious aspect to them but most state schools don't, and where else would you encounter religion unless your family were already into it?