No worries
And I was also hoping someone would bite as the obvious analogies are transfers like Mkhitaryan, Kagawa, Keita etc.
Players get bought after one good year in a specific setup/a specific system and then underperform - irrespective of the league.
Also I think people severely overrate the expected "success" rate of high profile transfer. I remember the discussion of which top 10 most expensive transfers of all time were actually worth it - the answer is pretty grim, so "underachieving" seems often to be rather the norm than hitting the ground running. But peope want to look into alternative causation to have a satisfying explanation for something that seems wrong ("We/they spent so much money on him and he doesn't perform")