And the arcane halo is just a blue halo, which means that the prismatic halo is pretty much the arcane halo is pretty much the polar halo, but without the snow? Or am I missing something?
The polar halo is the arcane halo, but now its snowing?
Yes, prismatic halo can essentially duplicate any halo if you have the right personal color.
And in response to your title... It's invalid, because not everything is possible to begin with. Not even counting impossible things.
Anything is possible within the restrictions of possible itself. That is, anything that isn't directly in breach of logic like contradictory statements or a paradox (but depending on the scope of "possible", an indefinite answer may not necessarily be an impossible one)
Some of the halos are on fire like the arcane halo, some are gleaming like the divine halo.
The Polar Halo lacks both of the gleaming and fire effects, in lieu of a misty, soothing highly translucent particle snow that looks absolutely dashing on frosty costume items, hiss.
Let us not forget, though, that crown of winter was a thing.
Polar seems, compared to that, to be much more than a little recycled.
I'm just surprised that this is worth so much, as its literally the same as 3 other items, but ever so slightly different.
I conclude that the Polar Halo is better than the Arcane Halo, I guess.
Item X with particle effect Y is the same as item X with the particle effect Z, its just that Y is different to Z.
All halos are the same. It's just different colors and stuffs.