Using Meteo to hurt Golbez proved only one thing: Golbez can be hurt. Gee whiz!
Also throw in the fact that until FFIVA, those who left the party left permanently, once you get Edge. Unlike FFV, FFIV doesn't get the luxury of having a cast where you can choose for them to do whatever they want. FFIV's cast had specific niches, and Tellah is easily replaced by the far superior and far sexier Rosa and Rydia, and the pedophile-licious Palom and Porom. Galuf's death just plain matters more than Tellah's.
Although, I will admit that it wasn't a series first. FFIIj did that well before FFV or FFIV. Hell, even FFIIIj lost Elia.