Repeated use of themes, characters, systems, flora, fauna, minerals, jobs, classes, story elements, magic, weapons, and transportation (and more) doesn't equal connected to you? Did you even read what I wrote? Or did I not explain it well enough?
That can be found in any series, for example the tales series, has recurring characters, but they are not all connected, outside of Tales of phantasia and tales of symphonia 1-2, every other single title is stand alone, yet they all have the same summons, same magic, same weapons, some character cameos etc etc. Breath of fire is another series that has many similarities, but is BOF IV connected to 1-2-3 ? No is V for that Metter.
There are only 3 FF main titles that have a connection, that is X-2, XIII-2 and XIII-3. Every other single title is a stand alone title.