Several years ago, the Vatican said the exact opposite and even declared that it would be permissible for the faithful to financially support the Society.
The Conciliar church has absolutely no stability. Even its own rulings are constantly subject to change based on changing situations. Clearly, this change was deemed necessary to put additional pressure on Bishop Fellay to accept the deal--and, apparently, it worked (or, more likely, was part of an overall strategy).
After the reconciliation, I guess they can start working on changing the TLM.