I don't know exactly if they're protesting against this (decentralized protests have this, everyone protests for their own reasons) but they pretend to write a law that will expropriate land if it's not used according to their ESG-like rules.
This is not the law per-se, but a paid study that signals a self made problem they can "fix": https://joint-research-centre.ec.europa.eu/publications/agricultural-land-abandonment-eu-within-2015-2030_en