I think that there is an official and an unofficial reason. The official is that something must be returned to nature before climate change destroys everything. The unofficial is, in my opinion, that EU politicians are terrified by US elections.

In all western countries, far right groups are crawling to grab more and more power gradually. Those groups feed basically on farmer followers, ruthlessly brainwashed with fake news, antiscience and outrage, and the system has proven to work well (See US).

Until now traditional parties believed that could control the situation and appease the farmers with more money, and maybe even benefit of some votes of grateful people on return. The wake up has being brutal. Each euro given to farmers is just a victory reclaimed by this groups, that nurture a higher discontent.

So now that they are coming for they political heads and the time is running out, traditional politicians feel the pressure to take some delayed unpleasant decisions before is too late, and getting rid of the fake farmers to build a market from there is a first step. If fake farmers can sell subsidized meat for a lower price, the real farmers suffer for it.