To add to it,

The hosting of EU-China summits traditionally alternates between Brussels and Beijing. The premier usually attends the summit in Brussels, and Xi hosts it in Beijing, but the EU believes the importance of this meeting — to commemorate half a century of diplomatic relations — means that China’s president should attend

So actually China is sending the exact same person who always attends the summit in Brussels. Which for EU means Xi snubbed them. Peak western diplomacy.