It wasn’t about stating a scientific conclusion. This is all that it said:
In formulating and implementing the Union’s agriculture, fisheries, transport, internal market, research and technological development and space policies, the Union and the Member States shall, since animals are sentient beings, pay full regard to the welfare requirements of animals, while respecting the legislative or administrative provisions and customs of the Member States relating in particular to religious rites, cultural traditions and regional heritage.
Religious conservatives, when they object to something as innocuous as “since animals are sentient beings” due to a fear of evolution, are being anti-scientific. But they and their allies may use arguments similar to yours to justify opposition, casting it as something for scientists to decide, so that the law doesn’t touch the matter. (So watch out for that.) What does it mean for a mind to perceive, to feel? Under what circumstances should we prohibit or criminalize the causing of pain in the mind of an animal? (And guiding statements are often part of the basic law of a country/union.) It’s just science?