With reference to the following paragraph
"All .eu domain owners would have to provide proof of EU citizenship – checked by the registry – before being allowed to register a .eu domain, it was decided."
There might have been some misunderstanding.
As of 19 Oct 2019, EU citizens will be able to register or keep a .eu domain name no matter where they are residing.
EURid, the .eu registry manager, will not request any proof of citizenship to enable a EU citizen to register (or to keep) a .eu domain name. Checks might be conducted ex-post as it happens at present.