I suspend a lot of belief for SPN, of course we all have to. We're not expecting “reality”, please, but I don't want to be thrown clear out of an episode because it's not being consistent with its own internal logic.
When I watch SPN, I can't help but do it through two different sets of eyes: one set watches with a deep love for the characters and the world they live in, but when the show doesn't seem to stick to its own rules—when something makes me go “Huh, whut?” or “Really?!”—I use the other set to consider outside forces that might explain why certain debatable decisions were made. (I'm not always in consensus with all fans, but who is?)
Sitting down for a re-watch, eh, maybe WS wasn't as bad as I'd remembered. Now that a lot of the fandom heat has died down, I can watch it with a bit more objectivity. It wasn't awful. Nor was it stellar. Yeah, Donna's accent is still over-the-top and Claire still isn't my favorite Sister. And the Winchesters' time spent in The Bad Place is still a bit of a stretch, in terms of how ineffectual the boys were made to seem.
I feel like maybe WS was so desperately hyped, there was no way it was going to live up to such high standards. The fans who want it to succeed, sight unseen, will champion the spin-off no matter how good or bad, and the fans who want it to fail, will pan it with equal prejudice. It's those in-betweeners like me who WS needs to win over, as well as the non-fandom viewing audience. I'm not sure it did that, but I'm also pretty sure it'll get picked up anyways; this is SPN's last best hope for a spin-off, and the network loves SPN and lordie knows, a female-dominant cast is timely.
Anywho, there's been much complaint about Sam and Dean being made to seem ineffectual so that Claire could swoop in and save the day. I don't think those complaints are wholly unfounded, and it certainly didn't help that Claire is unliked by a goodly chunk of fandom. (She's a whiny teen, she's just there because she's Castiel's vessel's daughter, yadda yadda.) If, say, Jody or Donna had been the one to do the actual rescuing of the Winchesters, I would put money on the whinging being greatly decreased.
So there's that.
But also, we're supposed to believe that Sam and Dean have traipsed around a dim forest for two days and haven't seen a brightly glowing, fiery slice in the fabric of reality? They know they're being tracked—they've heard footfalls and whatnot—and yet not-Kaia can sneak up right behind them and take them down, boom boom boom? (The boys are later shown to be armed with angel blades. And neither one could access those, during the fight. Oookay.)
Not-Kaia, seemingly alone, manages to drag two grown-ass men to some clearing x-distance away (it is notably an area the boys have not seen before), and stands them up, gets them tied to trees … and leaves them armed with their angel blades. (Why didn't she just kill them outright? To feed not-Cthulhu? Will we ever know?) It doesn't take Claire and our-Kaia long to find (non-glowing) Sam and Dean, which indicates that the rift wasn't that far away. Okay, sure, Jan. Then they cut the boys free, flee, but are apparently still being tailed by not-Kaia because as soon as they try to get through the rift, not-Kaia lobs her spear-thing at our-Kaia, and the group must escape without her. Blip, rift gone.
Every scene with the Winchesters was solely designed to set up WS. No surprise there. But the show took umpteen shortcuts and demanded that the viewer make up their own rationale as to why the boys were as failsauce as they were. (I KNOW, people don't say “failsauce” anymore, but if the slang fits...)
This practice drives me nuts.
From an authorial POV, I accept that they had to set up some quick way for Claire to easily rescue the boys. But from an in-world viewpoint, it just didn't fly for me. I will suspend my belief in monsters, in magic, in Heaven and Hell, because all that exists in the SPN universe … but the occasion that Sam and Dean both are both just routine fumblebutts, 'muggles' for all intents and purposes, is harder for me to swallow. If a little more cleverness had been used to craft their Bad Place scenes, I'd have enjoyed the episode far, far more.
(Full disclosure: yes, I watch the show for the Winchesters. It doesn't mean I “hate” any character, nor wish death upon the WS spin-off. I'm a no-kink-shaming, ship-and-let-ship fan. I am also a proponent of fanon being fanon, and canon being canon. We have our luxuries in fandom to do anything and everything under the sun; the show has far more constraints on its standards and practices.)