Is this about knocking down Python?
Or building a tool set for people who are currently outside the current ivory tower of machine learning and Python coding? Seems like this will grow a user base pretty quick, but not by cannibalizing people who are already super happy coding python by themselves.
This will succeed because it will allow people to integrate GPU acceleration into their projects without having to integrate as many build environments to code, test, and debug in. That was one of the advantages of Node, that you can take a common pool of the same programmers, and allocate them to teams on the back or front end as the project dictates.
Having to pay a separate python/gpu acceleration team, a server team and a front end team, then iron out the politics, integrate the stuff, and deal with the inevitable finger pointing when it breaks, that's the part that might be nice to avoid. Though the machine learning specialist may die a little inside when they get stuck writing a debug log chopper after the clever "AI" bits are coded up, instead of camping the Foosball table in the break room. (Shit, remember breakrooms?)
But at least the middle ware is in Rust right?