The Voice Master bot allows for users to join a starter voice channel and get moved into one created for them. It allows your channels to be scaled up or down easily without issue.
Here is their website: https://voicemaster.xyz/
It also lets users lock their channels, make them hidden, rename them, and more with commands. And what they can do can be tailored by the moderation team with ease.
I just tried joining the Discord to play and all the channels are full.