is astrill vpn good in china?
Yes it should be good. But probably you need to pay (the free Android version only get one server optimised for China and you can not change the protocol).
ExpressVPN is also pretty good. Both are the more expensive type.
12VPN can be another cheaper option.
You may be get cheaper ones like Surfshark and NordVPN to work as well with some tweaks. The app may not work but you may contact customer service to use alternative methods like OpenVPN servers to work.