@DerpyFast
In hindsight, in contrast to the lens I was viewing it under at the time, it was probably clear with The Summer Sun Setback that the LoD weren’t getting redeemed, with how the narrative was going. Grogar had
no idea what was going on, it was
their story of how they were toppling him up to that point, they showed no signs of second thoughts for how they were treating ponies (that bait and switch in Frenemies was just that), with Tirek complaining about returning stolen magic, without any empathy to his victims, Cozy still enjoyed being a saboteur manipulator, etc.
There’s also this foreshadowing from The Beginning of the End, that Grogar wasn’t gonna be the ultimate Big Bad on his own:
Spike: And it worked! I mean, if you think about it, there hasn’t been a single villain that we couldn’t defeat.
Which if they were building up to those three attempting a backstab from the end of Frenemies, was probably only ever going one way.
It was also odd how Discord was suspiciously uncharacteristically involved in the S9 premiere (aside from any oddities Grogar might’ve had in general); Discord is never involved in premieres or finales (and seldom is he not causing the issues even in regular episodes) unless he directly has something to do with what’s going on, or he’s personally invested in some way (Fluttershy was captured in S6, and it was a ceremony in the S7 premiere, the rest he directly caused it), and it would’ve been odd for him to start then, if he wasn’t doing it for the Movie, or S7’s finale, or S6’s premiere, or S5. He also seemingly had no real reason to be there in The Summer Sun Setback.
I’ll also note that the last two-parter itself had other sorts of story fuel regarding those three; if they won, Chrysalis was probably not gonna stick with the other two at that rate, past victory, because her MO fundamentally differed from theirs, aside from “baby alicorn is being set up to try to save the world later,” and Cozy Glow kinda wanted to seize control from them.