Take, these broken wings, and learn to fly again... using more interesting methods...
Broken Wings is a small, simple mod that allows packmakers to disable creative-mode style flight in certain dimensions.
The default config options disable flight in dimension 7, the default dimension ID of the Twilight Forest.
Additional configuration options are available: you can whitelist or blacklist dimensions flight is allowed in, you can blanket-ban flight in all dimensions, and you can optionally choose to cancel Elytra flight. The mod can also send messages to players when their flight is cancelled and/or create a server log message.
This work is dedicated to the public domain.
Questions? Comments? Just lonely? Join me on Discord: https://quat1024.github.io/discord/