It will be a tremendous technical feat if they have managed to bring the deep functionality of what were Weta's internal tools to a more general audience of artists. The key difference will be that these artists won't have direct access to the developers who wrote the tools, as the Weta artists did.
Packaging powerful graphics tools within an artist-friendly interface and workflow is challenging.
It says "Contact us", which probably means tailored license and support, and feedback of bugs/wishes, from a few selected clients.
Epic not only develops Unreal, but also develops games and is deeply invested in building stuff for the movie industry.
Unity... Well.
I mean, they both are. That's the whole point of this post here, to show Weta and Unity and the tools they have for movie makers. With your "Unity... Well.", what did you mean? Weta and and Unity aren't doing this?
It's good that Weta/Unity has competition now with Unreal and vice versa. We've seen what happens when one entity controls nearly everything (Looking at Autodesk here).
If the button says "contact us" or they ask for a waitlist, they haven't actually built or prepared much for release and are gauging for interest before likely starting to take engineering etc action on it.
Caveat: things may have changed a bit after my time.
I don't know how accessible or useful these will be to most game devs using Unity (apart from maybe Speedtree).
As far as I've seen, neither Unity nor Unreal have moved in this direction. Their "sequencer" solutions are IMHO unwieldy kludges that don't take advantage of new higher levels of abstraction for producing computer animation.
From the sign-up page, this also doesn't seem to be a general access sort of thing. They want early adopters who already know a lot about this field of technology in order to give feedback and detailed bug reports.
Heck, even NerdForge used Unreal to create their virtual window on their new set. https://youtu.be/Vg1TGADF248?t=880
So instead, fwiw, anecdote: I work for a film production company and we ingest assets all the time from high end VFX houses. It's always from Unreal / used in Unreal in my experience. That's in LA/ Hollywood and high end productions. For all I know they use a lot of Unity in Bollywood or Europe.