The claim is too absolute. At the time, most EU laws were made through the ordinary legislative procedure, in which the European Commission proposes legislation but the European Parliament and the Council can review and amend the text, and a law is adopted only if they agree on the final wording. The European Parliament also describes this as joint law-making that gives it power to shape EU rules and policies. So it is not true that in the European system you cannot change anything, even if the Commission has the right of initiative. (commission.europa.eu) Sources: European Commission, "Adopting EU law" (https://commission.europa.eu/law/law-making-process/adopting-eu-law_en); European Parliament, "Legislative powers" (https://www.europarl.europa.eu/about-parliament/en/parliaments-powers/legislative-powers); Council of the EU, "The ordinary legislative procedure" (https://www.consilium.europa.eu/en/council-eu/decision-making/ordinary-legislative-procedure/).