From what I remember, Cassidy was more than a passenger in her alliance. She wasn't the big out front boss of the alliance, but she was a key part of it and wasn't just taking instructions on who to vote for. I would say she was a little like Kenzie with her agency within the game. I felt like the weird situation with Carla overshadowed that she played a solid social game. She seemed to get along with virtually everyone else on that season, and it seemed like she got along with Carla for a long time, and that she didn't do a whole lot wrong to cause Carla to have such a vendetta against her.
I didn't dislike Gabler. To me, he was a slightly better version of Ben. He was likable and got along well with almost everyone. He had no real agency in the game. Wasn't a complete dud in that they were dragging him along to the end, but he was kind of just there. They keyed him in on most things and weren't trying to target him, but he wasn't viewed as a threat to anyone and he wasn't really part of much of the decision making process.
I'm not saying there was a huge difference between the two. From my rough memory, maybe Cassidy was like the 5th best on that season and Gabler like the 9th best. But it felt like, using a term you used last week, "on paper" that Cassidy played the better game and the jury awarded it to Gabler because Cassidy wasn't who they wanted "representing the season" as the winner. A lot of that felt petty, personal, and bitter. It wasn't completely that this season, but it was kind of similar in that they seemed to know who played the better game "on paper", and there wasn't any huge villain in the running, like a Russell, and they simply went with who they preferred to "represent the season" as the winner with maybe the only touch of bitterness or pettiness coming from Maria, who lets face it probably did decide the winner based on her vote.
I don't think Cassidy played a better game on paper, unless you value immunity wins, which no jury really does unless they win out like say Mike Holloway where its undeniable. Gabler actually drove a vote, replaced himself in a better position, then played a pretty solid defensive game of keeping votes off him, and he spoke to that.
Gabler's move which he could point too was he was at the bottom of Baka at merge, reshuffled the pecking order knowing he had to idol to burn the next week if things turned on him (since it had an expiry date, and the played free agent). Played free-agent, and then identified where power resided (Jesse and Cody). Following that he worked closely with them (although badly edited), but he was in a tight 3 with them.
The thing the edit didn't really capture was, outside Owen and James, most of the jury didn't vibe with Cassidy, from pretty much all exit press outside maybe Jeanine. Whereas they generally liked Gabler. I think liked Owen, but they didn't respect is game at all since he made nothing happen. Cassidy was pretty much on the bottom of her merge tribe with Ryan, and stayed there all game, and was again at the bottom of the Jesse/Cody/Karla partnership (which not realizing both Jesse and Cody were closer to Gabler than her).
Cassidy made a ton of missteps. She overvalued her position on a strategic level, she didn't drive any one else's vote, you absolutely make the jury bitter if you claim their moves as your own. Gabler basically understood where he stood, stood up for why he made the moves he did, but most importantly, spoke to every juror on how he worked with them.
I think Jesse/Cody/Karla played better games. James played more from upfront but that can easily get you burned. Noelle would have been a massive jury threat and had a cool move.
I'd say Gabler's game was more impressive, especially when he basically roped Owen and Cassidy in on that exact final 3 which for somereason was never show. My guess is editors were pissed they didn't get the Jesse win. I think a lot of people confused Cassidy's game with Erika who only won a bit prior, but Erika actually took over the end game, Cassidy didn't really.