This is a subjective question and the answer won't be the same for every single viewer, but here's what we think:
Is RWBY: Ice Queendom Good?
If you liked Rooster Teeth's RWBY, you'll likely find RWBY: Ice Queendom fun.
It's about all the beloved characters, and it expands some backstories that the original left underexplored while featuring a fresh and original adventure.
This new adventure will appeal to those who enjoy psychological anime and peculiar symbolism.
Puella Magi Madoka Magica and Wonder Egg Priority come to mind, though, to be honest, Ice Queendom alone doesn't reach their levels of emotional intensity (the original is a different story).
Ice Queendom has 2D animation which you might love or find hard to get used to, depending on your feelings about the original's 3D animation.
Ultimately, there's nothing particularly off-putting about RWBY: Ice Queendom.
Is RWBY: Ice Queendom Bad?
This isn't entirely the show's fault. The original RWBY anime itself felt like a cheerful school anime series until the end of Volume 3 when things became really dark very quickly.
The issue with Ice Queendom is that it doesn't give enough novelty to existing fans and doesn't stand on its own well enough to recruit new ones.
In its attempt to re-introduce the show to anyone unfamiliar with it, it created three episodes that summarize a RWBY Season, adding interesting but not groundbreaking information.
The new adventure is a cool and unique idea with interesting symbolism, but it's understandably not enough for everyone -- all the more so because it unfolded in a dream world.
The "it was all a dream" trope isn't as appealing as it used to be, and, even when it's done in a cool or self-referential way, some of its impacts are lost because the consequences aren't all that tangible in reality.
Understandably, this is what Ice Queedom had to do, as it would probably be difficult to fit an adventure that wouldn't somehow negate the canon in major ways.
Perhaps RWBY: Ice Queendom would have been more effective if it unfolded as a shorter OVA as opposed to a whole anime season that many found repetitive after a while.
Related: When Is RWBY Volume 9 Coming Out?
Is RWBY: Ice Queendom Better Than the Original?
Based on the above, we don't think that RWBY: Ice Queendom is better than the original. However, this is not to say that it is bad; it's simply a matter of taste.
If you enjoyed the original, by all means, check out the new Shaft anime and decide if it's for you.
If you started with Ice Queendom, we recommend trying the Rooster Teeth anime whether you loved Ice Queendom or not.
The original animated series tells a layered story that unfolds beautifully and grows along with the creators and the Rooster Teeth company.
Given that, the original may be hard to surpass. But it doesn't mean that anything else that comes up in the RWBY universe won't be worth watching in its own way.
Related: Is RWBY an Anime or Cartoon?
For more articles like this, take a look at our Anime page.