A user filed a bug for discord.js where a previously functional input no longer worked.

Boiling down the issue to its most minimal form (past all the nested union and intersection types), the difference boiled down to this:

The issue still occurs as of 4.4.3:

For now, I decided to fix it by replacing the predicate with

choices: z.array(z.any()).length(0).optional()

See discordjs/discord.js#11532