Remember the bizarro-world version of the DHMIS "Traffic Light Trio" in which Duck is Red, Yellow Guy is Green and Red Guy is Blue? Well, what do you think ever happened to them?
With the new series coming out, and the return of the original trio, I feel it is currently unknown what happened to the RGB trio that we saw. They seemed to have been scrapped altogether.
Unless it will be revealed in the new series, I feel that we should discuss what we believe happened to them (as well as our thoughts on their disappearance).
My theory is that considering that the Sketchbook was shown at the end singing "What's your favorite idea?", the RGB team probably took the TLT's place as they are now in a world called Clayhill. Now the RGB team are the ones who have to endure the incarnation of the original singing objects. Whether they're as insane as before or perhaps a lot better is unknown to me. Either way, it seems that they're the ones stuck in their place now.
But as I said, perhaps the series will reveal their fate and maybe we'll see them again. Who knows?
Feel free to add on your theories and/or ask me more about mine.
There are two theories I wish to accept as true, the first being the well known media theory best described by night mind, and the other is the very unknown one that it is about red guy growing up and abandoning his imahinary friends (red and duck) and accepting the world may be a bit less fun now.
First, the media fitting.
The three characters in clayhill are now in adulthood, they now face new problems, ethical concepts, instead of being the good guys, duck seems to be a bit of a jerk, while red guy doesn't understand childish concepts, seemingy getting very annoyed at the mayor simply playing make believe. Yellow guy is a bit young, so be is being corrupted by fizzymilk, turning into a commercial machine.
The RBG trio are the new generation, the new 3 friends now learn more friendly lessons from revised teachers, they reprisent a better future for society, one in which people are taught properly, the series repeats with the coorperate machine off, leaving them to be themselves
Then, we have the growing up theory.
Red guy has gotten his own home, but he now can't abandon his friends. Clayhill is his final attempt to keep himself from the world. His own town, entirely made up of his friends. Red guy was unable to cope with losing his childhood, so he isolates himself further. The new story is much more like a children story, with less grossness. Red guy is stuck inside of his own mind, and someone is going to need to get him out, and love him or hate him, roy is the one we need.
As for the RGB trio, they're the next generation, growing up with the new toy brand, newly coloured with cool designs.
Growing up theory is unorthodox and unpopular, so sorry if this made little sense. I think they're both very good theories, so I decided to cook up a potential fate in both scenarios.