Actually I suggest two things: Firstly, use a container to run Minecraft server is a more secure mean. Using docker is a good idea. Related Docker images can be found on docker hub. Secondly, using a web interface is a good idea. I used MCS manager. Link here.
The page like this should not be a government department to prohibit access to this website. If they really do it, it should also appear a prompt similar to connection timeout instead of access denied. Someone said in MCBBS, it is possible that someone(or a server) trying to attack the server(May not deliberately) to lead China's network operator's IP is automatically banned.
Obviously, every Chinese user crosses the firewall is very unreal, after all, this cost is high, and this may not legal, it will cause a lot of trouble. I think the best way is to ask the Spigotmc team(or community). Ask them what caused this is a good way to solve this problem. (note: I can't access spigotmc website either.) (note 2: I think everyone in China user forum (translate may needed) is waiting for answer.) (note 3: other websites protected by cloudflare like steamdb is visible in China.)