Zig and Python/Java are completely different beasts. One is a low-level systems language on the order of Rust or C. The other two are much higher level, easier to work with languages more attuned to desktop, mobile applications and enterprise work.
I don't think anyone is seriously "jumping ship" from Zig to those.
Low-level programming isn't the holy grail. If a person gets fed up with limitations of C, they might as well move to a higher-level domain area as well. Especially, given the higher pay there.
Those who haven't will have a much lower tolerance for changes. Survivor bias of a kind.
It's not really a choice of low-level or high-level. Neither is better than the other.
It's about choosing the right language for the task at hand. Some work will really be suited (or only be feasible) with a low-level language and vice-versa.
If I'm writing a command-line tool on the order of ripgrep or working on a microcontroller embedded in a dishwasher, I'm not going to go to Java. That would be weird and awkward. And if I'm writing a new 3D AAA-level game, I'm going to jump to something maybe even higher level like UE5 - trying to do all that in Rust would be a PITA.
I don't think anyone is seriously "jumping ship" from Zig to those.