You must be unlucky, according to Openreach "fibre broadband is already available in more than 96.59 per cent of the UK."
They lied a lot for a good few years saying "OMG fibre broadband!" When in reality is was still copper for the last mile so that "fibre" connection in reality was some ADSL variant and limited to 80/20mpbs.
Actual full fibre all the way from your home to the internet is I think still quite a way behind. Even in London (London! The capital city with high density) there are places where there are no full fibre options.
[1]: https://www.thinkbroadband.com/news/10343-85-gigabit-coverag...