The reason for this is lack of HGV drivers, right? But this HGV crisis is not exclusive to the UK. Europe are having similar problems, in particular Poland and Germany.

Brexit is clearly a factor, but it's nowhere near the primary cause. Apparently the govt have written to a million HGV license holders asking them to consider returning to the sector. That's a huge number of people who have chosen different jobs, around 2% of the working population. That's an insanely high number of qualified drivers we have. This is solved by making HGV driving an appealing career, and we do that by increasing pay, improving facilities and improving working conditions.

If Germany and Poland are avoiding this sewage problem, then that probably means their governments are doing a better job of managing the HGV crisis. This seems to me government incompetence, not Brexit.