Thanks for the paper. I've had a skim through but will have a more in depth read later in the week.
It's still somewhat relevant to the UK.
Although Virgin intend on overbuilding their DOCSIS with XGS-PON it will take many years to complete.
Virgin will run both networks side by side for a number of years and they still intend on upgrading the DOCSIS upstream path to 3.1, including physical work on the node splits.
Some of that work has started.
I very much doubt we will ever see DOCSIS 4.0 in the UK but the cable network isn't quite dead yet.