For context: AirDrop was one of the only ways protesters had to communicate en-masse.
Signal is unsafe for Chinese protesters, since it requires SMS verification upon signup and is therefore linked to your identity.[0] Mesh networks are the only real solution there, and AirDrop is about the only mainstream one. AirDrop has been used by Asian protesters for years.[1] I highly recomment you read the full China Digital Times article, which gives excellent context, and lets these protesters explain the value of AirDrop in their own words.[1]
Apple's timing is unmistakeably suspicious; keep in mind that there have been protests for weeks, which preceded the iOS update.
It must also be pointed out that Apple issued an official statement to Western media outlets that the goal was to prevent spam.[2] At no point did Apple ever admit that this was done to follow any government demand. It's unknown whether Apple could be under a Chinese gag-order, but we shouldn't speculate that it's the case unless experts say it's likely. If Apple is complying with a Chinese government orders, then it has an ethical duty to make that public, and again, we have, as of yet, no reason to assume there are gag orders related to this. Apple deserves criticism for the update, and for trying to hide its true purpose.
[0]: https://twitter.com/RealSexyCyborg/status/159707255662827929...
[1]: https://chinadigitaltimes.net/2022/11/netizen-voices-apple-r...
[2]: https://www.bloomberg.com/news/articles/2022-11-10/apple-lim...