As much as I find the Palette interesting, I see some issues. It will most likely work best with filaments that need very similar printing temperatures. Otherwise, how will the nozzle heat up & cool down quickly enough? I think that’s a serious limitation.
Also, how much more likely is it that clogs will occur because of the different materials. I have found, in the 1 year+ I’ve been 3D printing, that mixing PLA & PETG through the same nozzle causes more issues than it’s worth, so I don’t do it any more. In fact, I’ve pretty much settled on printing PETG.
I find multi-color printing a novelty and agree that a good IDEX printer would be a better option. Here is why.
In general, when manufacturing multiple color or multiple material parts you produce them separately and then assemble them with nuts, bolts, glue, etc. Think about most furniture, plastic toys, even art.
In other cases, you paint or color the product after it is produced. A good example of this is pottery.
Now is special cases like a laminate wood cutting board you may glue the materials together and then shape them this is the exception, not the rule.
I think the best use for multiple-material 3d printers is printing supports in one material and the main body in another. This allows you to print much more complex parts and if you are using dissolvable support material to remove the supports easily.