Most of the plot in FFXIII felt pretty irrelevant in FFXIII-2 though. Only thing that seemed important was the epilogue.
We can go for hours if you want talking about this.
Long story short though is that XIII wasn't a trilogy at first but then XIV 1.0 and other shenanigans happened at SQEX and the story was expanded. Was that bad? No. Should people be all nitpicky about it? Yeah why not, but you know how opinions work in the Internet.
Point is that the story was expanded in a nice way and the connection of the three games goes as far as it need to go to leave every game to be its own thing in the process.
Didn't mean it in a bad way. Just saying that Klyde will not be missing much if he goes into FFXIII-2 without having a great memory of the first game.