How is that relevant to this discussion?
Unity is a requirement of the Church, and any intentionally actions to create disunity are forbidden. Having read some comments about the Franciscan case, and now this case, a concern mentioned was that those offering the Tridentine Mass were using the form as a sort of protest, almost a passive-aggressive statement. If, and a big if, that is the case, it would make sense for the local ordinary to forbid it use, by the “offending” parties, though not for the diocese as a whole.