The part of that statement people are disagreeing with strongly is your assertion that Rey flopped in the arena weeks after release.
This is objectively not true, as backed up by facts.
Citing facts like the arena report that say no, Rey did not flop in the arena after you say Rey flopped in the arena is not an attack, is not nitpicking, and is changing what you said. It's disagreeing with you.
And Rey flopping in the arena is the foundation of your argument. The basic assertion of the very post you quoted was, "Rey flopped in the arena, so they tailored the Sith raid to her to make her useful."