I would consider California screamin to be a large exposed steel coaster. Now, we can of course argue that this ride can get away with it based on how it fits within the theme of paradise pier, and compare that to how the slinky coaster will fit/blend into the theme of TSL.
And I am not excusing the slinky coaster. I don't like the lack of details...
I've heard that justification before, but I don't necessarily agree with it. California Screamin' is a steel coaster pretty heavily and convincingly themed as a classic wooden coaster, which fits well into its setting on a classic seaside amusement pier. Now, we could definitely argue the merits of theming a roller coaster as a different kind of roller coaster or even of an area in a theme park that is themed to be an amusement park, but the point stands that it fits well into the fabric of the setting that it's in. It meaningfully contributes to the story that the area is telling. It feels natural.
I'm not directing this next part specifically to you, as I realize that you're not in favor of this coaster either. I just see a lot of forgiveness going on for something that honestly feels like a terrible backwards step for the parks.
Slinky Dog Dash is a different animal from Screamin' altogether. The Toy Story theme is honestly so secondary and serves no real purpose. Andy never owned a coaster playset (to my knowledge), and he certainly never had one that used his Slinky Dog as a car. It feels very forced and unnatural. Especially now that virtually all of the themeing that it at least did have seems to have been removed from the budget, not to mention the one thing that was meant to hide the majority of the track.
The whole Toy Story Land thing doesn't sit well with me in the first place. The story of the entire area feels so contrived and overdone that it's almost sad to me at this point. We're in Andy's backyard and he's conveniently playing with toys that look like theme park rides. It's always the same thing with these Toy Story lands and it always comes out terribly and cheap looking.
Well it does appear to have some themed elements and Disney has already built Primeval Whirl, Branstormer, Goofy Sky School, and of course California Screamin' so while it's not the best option I'm pretty okay with it.
Those are all relatively small minor coasters (minus California Screamin'), and are all much better disguised than this. See above in regards to Screamin'. I think that's a pretty poor example of an "exposed steel coaster."
ANYWAYS, I know... tl;dr. I just have a lot of passion for the integrity of these parks. Occupational hazard.