Hmm. What kind of platform do you mean? We sort of have 3 domains: probing, electronics measurement, and test control.
There are probably a few electronics measurements efforts out there. Maybe EEZ-DIB is worth a look as a platform? And Black Magic for JTAG programming/test?
Test control is, I suspect, often a code-your-own effort. The EEZ crew are working on graphical stuff like EEZ-Studio and EEZ-Flow; I don’t know if that’s helpful.