We need psutil to handle backend process management, ie allow the user to terminate long-running backup or restore job. I don't see any alternative to psutil at a moment which supports cross-platform process management like psutil do.
I think the reason why there is no binary wheel is that it is hard to maintain platform specific binary wheels.
It looks like the most recent release of pgadmin4, 3.5, added a dependency on psutil==5.4.7 . This dependency is a bit painful, especially for me, for a few reasons.
First, it needs a C compiler to build. Second, upstream is not providing a Linux binary wheel, manylinux or not, to help us out here. Third, Debian stable ships with psutil 5.0.1 but you have a hard requirement on 5.4.7. Finally, I tried building my own wheel on what I thought was a similar system but my pgadmin4/apache is segfaulting (although this may not be the fault of pgadmin4, I am unable to rule this out).
So I'd appreciate some feedback here, if you happen to know what the best way to troubleshoot this segfault in pgadmin4 that would be great. But for sure I would also ask you to consider relaxing the dependency on psutil given that virtually all users of your package now have to maintain a compiler and wheel compilation toolchain somewhere if they want to run pgadmin4 on Linux.