I think the EU issue is to avoid LH and AF (and BA as it is now Spanish owned not British) from being screwed over any more by the ME 3 pirates with their once bottomless pit financing. They are gradually having to adjust to the realities of lower oil prices and this si the time to hit them hard.
The Eu are not that bad on airline competition actually after all EZ FR and Wizz do pretty well and have materially impacted pricing in UK. But its one thing these Eu upstarts taking revenue from BA LH etc because they are still EU companies but the ME 3 are not .
As for the APD argument -well if the ME3 disappeared the pax would still be going but on an EU carrier instead so that revenue isnt lost to any government