– “I still really struggle to understand why we so much worse, than our near neighbours.”
My guesses are (1) the UK started vaccination earliest, so immunity is fading in more people earlier than elsewhere; (2) Westminster removed all restrictions, whereas most EU countries still require masks in closed spaces and restrict the size of indoor gatherings among other things; (3) other countries have paid more attention to ventilation; (4) Westminster’s schools policy is guaranteed to spread infection, as you’ve pointed out yourself; (5) UK testing can’t be targeted well because infection prevalence is too high – other countries find a greater proportion of their positive cases with less tests because their trace-and-test is more successful.
But these are the issues covered by the links myself and others have been posting in reply to your repeated questions on this subject.