I just logged onto the Swiss Post's website and saw a bright yellow popup with the following message:

Swiss Post no longer accepting letters and parcels addressed to China in its branches

Many international flights to China have been cancelled due to the coronavirus, and this restricts the sending of mail. For this reason, Swiss Post is no longer accepting any letters or parcels addressed to China in Swiss Post branches or branches with partners until further notice.

That is incredibly unfortunate and very saddening. I think it's also kind of worsening the situation for people stuck in China. If the postal services in other countries also follow up on that, the people affected will be left with no mail to possibly cheer them on in such a situation.

Please if you are planning on sending out mail to someone in China, do it as soon as possible, while your post still accepts them.