theres no potential for TFT to get its own client? like its not a different game mode like aram or treeline, its a completely different game
It's not impossible we do so some day. TFT and LoL MOBA share an awful lot of functionality though. Disentangling the two would mean a substantial amount of dev time as a result. From the player perspective that means the benefits from separating the two would need to be higher than the benefits from having those same devs work on other stuff for both TFT and the MOBA side (new features, bug fixing, performance improvements, new content etc).