I don’t really know why you think it isn’t.
So, which of the chord types CAGED is based on covers the shown chord?
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Anyhow, now that we're at it already, let me say some things (it might even help understanding why I came up with this thread):
The idea of the CAGED system is taking typical open position chords and moving them around the fretboard, usually replacing the nut with your index finger. And yes, I know it's not *that* trivial, but that's the gist behind it.
Pretty much like your full barre chords, just expanded.
You would then alter them just as you can alter your open position chords. Such as by adding/replacing some notes, kicking off things you don't need, etc.
Don't get me wrong, it's still not exactly a bad system.
Also: If you played the very same triad on a different set of strings, the CAGED approach would tell you they were deriving from different "base" chords. For instance, these two contain exactly the same notes:
The CAGED system would likely tell you that the one on the left is deriving from an open A chord whereas the right one is based on a C or D.
And that's where things are getting smelly IMO - or at least start to fall extremely short in comparison to a more or less "universal" approach such as building triads.
So, what CAGED is lacking of is a certain "generally valid" approach in terms of building chords. IOW: The CAGED system is absolutely guitar centered and can't be transfered to much else, unless you go through quite some hoops. Which might still be fine as well. However, it's lacking of some things - which is why I came up with the chord above, which isn't covered by any moved C, A, G, E or D open chord form - or rather: you'd really have to go through the mentioned hoops to get there. But it's nothing else but the first inversion of an A major triad. Which, once you've invested a little bit of time, is instantly available through the "triad mindset" (lord, how I hate such buzzwords...).
In addition, you can transform all the triad knowledge you might've gained to, say, a keyboard instantly. Or write some horn parts. Simply because triads, their inversions and whether you play them in close or spread forms are something that can be considered a more or less universally usable part of the musical language.
Another thing I often noticed is that when people are trying to get more out of the CAGED system, they will at some point end up in "reducing" the full enchilada. "Uh, sorry, to create a comfortable to play minor version of that C shape we need to leave out some notes/strings!".
Which isn't even all that bad, but you still start with something that you don't exactly need - or can't even play consistently any longer. A full open C chord shape has 3 major thirds in it, for all of them to become minor thirds, you'd need more than 4 fingers and still twist them.
With the triad approach, it's kinda like the opposite. You start with the barebone basics and go from there.
Now, one thing needs to be mentioned, though: There's *always* more than one approach to these kinda things. There's also not exactly a "right" or "wrong". And you may even end up with everything I will ever play in this thread also being accessible through the CAGED approach (even if I sort of doubt it, see the chord I posted...). So, in a nutshell I'm just trying to present one way of doing things - but IMO it's a way that can be explained (and understood) properly and holds a lot of water within a sort of generalized musical realm.
And having said all the latter: So far I have possibly covered 10% of the things I'd like to cover in this thread. We're still on first steps level.
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