In Japan it never had the SMT moniker. The first game was titled "Megami Ibunroku: Persona" in Japan. Megami Ibunroku means "Strange Tale of the Goddess". The original English release (the butchered PS1 version) was titled "Revelations: Persona", but that was before the SMT name was used in the west. Persona 2 and onward in Japan didn't have a prefix to the title, they were just "Persona 2: Innocent Sin/Eternal Punishment, "Persona 3", and so on. They were implicitly related to SMT in Japan, but aren't SMT. In the west Persona 3 and 4's original releases were branded with the "Shin Megami Tensei" name, as well as Persona 1 on PSP. This was dropped for P4G, P5, and all the spinoffs that were released in the west.
Interestingly enough, Tokyo Mirage Sessions #FE was titled "Genei Ibunroku #FE", translating to "Illusory Revelations #FE". Given the title's vague ties to SMT in Japanese, it was fitting that it was *somewhat* tied to SMT, but not really an SMT game. The title becoming "Tokyo Mirage Sessions" (SMT backwards) was a really good localized title for the game.