The code in GameplayTagContainer.cpp has code for generating debug strings representing tag queries. Compare the code in EmitTokens in all other queries to the code in UEditableGameplayTagQueryExpression_NoTagsMatch::EmitTokens and you'll see that it is missing a prefix string that is present in all other query expression EmitTokens.
In other ones it is ALL( or ANY( and in the NoTagsMatch EmitTokens it should probably be NONE( but any kind of prefix is missing, despite the suffix ")" being present.
Compare the EmitTokens function for UEditableGameplayTagQueryExpression_NoTagsMatch to all other tag query expression implementations.
There's no existing public thread on this issue, so head over toAnswerHub just mention UE-66080 in the post.