Why would you forbid it? At most I'd consider it reasonable to have a little warning if you have the status hidden but their discriminator set to #0000, but even that feels sort of redundant.
Seems pointless to you, perhaps. Maybe there's some visionary who likes the #0000 discriminator, but thinks the design of the badge is ugly/clashing with the rest of their profile?
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Comment by @TheNamlessGuy
Comment by @TheNamlessGuy