For example, on an FX2 device, doing 24MHz sampling with 16-bits is illegal, and the message will be printed to the command line, but there is no way for a GUI application to receive this information.
Does this still reproduce with recent versions? IIUC Pulseview now hooks into
the library's logging, and users can lookup the cause behind "generic" errors
in the log window. Granted it's not as obvious and "in your face", but available.
Does depend on library code to emit useful messages though, that's also true.