It's not a good look, period. First off, all the focus on how non-Baltic Eastern Europe feels, when the ambassador's comments could also be intrepreted to apply to the Caucuses and Central Asian states, the latter of which China has been working tirelessly to win over ever since Russia got bogged down in Ukraine.
But this ambassador's comments also comes right off an incredibly succesful summit with Macron where deals were sealed and he casted doubt into the West's unity when it came to Taiwan. Granted interests run deaper than what the headlines publish, so hopefully like other Chinese PR cock ups this one will be forgotten quite quickly. But the ambassador should be at the very least immediately ordered to offer an apology, which is generous since the best course of action would've been to sack him.
Although I am not a fan of what the ambassador said. Most Eastern European nations have insulted China in one way or the other. Many of Eastern European nations have sent their parliament members to Taiwan. China should give zero regards to these Eastern European nations and how they feel until they stopped trying to interfere in the Taiwan issue which is the China RED LINE.
Cacuses and Central Asian States are silent over this topic. I am not sure if they care. If they do care, Chinese ambassadors in these nations should explain and reassurance them that China's position is always supportive of territory integrity.
Macron's meeting might be good. But German PM and the rest of EU have made sure that things went bad quickly. China isn't going to sit around and waiting for EU to come to its sense. EU won't come to its sense until Ukraine war waging on for a few years that no end in sight and EU's economic and inflation and suffering have not been alleviated. All of recent moves are China's last ditch effort to avoid a full blown meltdown with relationship with EU. Carrot and Stick, don't always count on carrot to work. Stick is needed. If EU nations are going to interfere in Taiwan, then all gloves are off. That means China will supply Russia with weapons and much more.
No apology should be offered. China is a sovereign nation and its ambassadors have the rights to speak their minds. China might offer clarity if needed for its official position on some topics if necessary.