I Don't Need Lila's to be an Actual Master Manipulator
I've spent a lot of time talking about the issues with Lila's writing, so I wanted to step back and talk about reasonable exceptions for a character like Lila. My stance is not that the writers needed to create a true master manipulator for her to work. My stance is that her writing only needed to be strong enough for me to suspend my disbelief.
"Suspension of disbelief" is the technical term for an audience being willing to play along with whatever BS the writers are feeding them. It's most often referenced in stories with magic as magic obviously doesn't exist. To enjoy a story with magic, you have to be willing to suspend your understanding that magic isn't real. If you can't do that, then you can't enjoy the story.
Suspension of disbelief applies to far more than magic, though. Stories are full of absurd coincidences, insane luck, and non-magical things that wouldn't work in real life, all of which require suspension of disbelief. Lila's lies are a perfect example. As far as we know, they're not magical. She's just a really good liar. The writers presumably know that they're not writing her like an actual good liar. They're asking us to play along and pretend that she is one. Here's the question: is that a reasonable ask?
Suspension of disbelief isn't a carte blanche to write whatever you want and blame the audience if they won't play along. It's a contract between the audience and the writers that the audience will play along for the sake of the story, but the writers still owe the audience their best effort. If the writers give a character that is so poorly written that the vast majority of the audience can't believe her supposed role for a second, then the writers have failed. This is where Lila falls.
The problem is not that Lila's lies aren't master class in manipulation. A show meant for young children was never going to give us a true master manipulator. Lila was always going to be simple enough that a child could follow her lies and the adult viewers always needed to be willing to play along even if the lies weren't that good. The problem is that the lies feel like the writers weren't even trying to make Lila work, a stance that is shared by a large number of viewers given the overwhelming amount of Lila salt in the fandom. Most plausible Lila take downs feature something as simple as a character talking to Jagged Stone about his cat or Rose texting her friend Prince Ali about his good friend Lila and learning that he's never met Lila.
When it's that easy for fans to spot ways to take Lila down and canon never acknowledges the problem, then the issue isn't fans asking for too much from a story. It's a story failing to even try to let fans engage their suspension of disbelief. This is why I often suggest fixes as simple as changing Lila's lie from "Jagged Stone wrote a song about me after I saved his cat!" to "I met Jagged Stone backstage at his latest concert." Neither of those lies is particularly impressive, but the second is strong enough for me to play along. The first is not.
When it comes to suspension of disbelief, there's always going to be an element of subjectivity. Every person has their own level where the BS gets to be too much and they can't enjoy a story, but I do think the average person is willing to give writers a good amount of grace. We know that any given writer probably isn't an expert scientist or a master manipulator, but we also know that stories need characters like that, so we go into stories with those kinds of characters expecting that there will be some weak points. There are stories where those kinds of characters need to be extremely well done for the story to work, but in many cases, that's not true! We know the hacker isn't actually hacking into a bank, but we'll play along because showing accurate hacking isn't as fun to watch.
I can think of several stories I adore where a character is supposed to be a master manipulator, but the writing falls short of that goal, yet I'm willing to play along because the lies work well enough. One of my favorite characters - Gen from Dr Stone - is a master manipulator with several scenes where his writing falls short of that goal yet I still love him and think he works well enough for the show he's in.
Even when my suspension of disbelief breaks to the point where I can't enjoy a story or plotline, I can usually see that the writers were trying, it just didn't work for me. I can name several stories that I found extremely silly where I'm quite critical of the writing, but none of them annoy me the way Lila annoys me because all of them feel like the writers were at least trying, they were just in over their heads. Lila is the rare case where the lies are so low-effort that they feel like an insult and that is my issue with her. I didn't need her to be a true master. I just needed her to feel like she was written by someone who respected the intelligence of the children the show was written for.