Modern DFDRs can record hundreds (if not 1000+) of parameters - way more than the minimum required set, plus they have the QAR (which may record even more) for almost all of the flight (including through the onset of the problem).
Kind of like a computer with a hundred USB ports for data inputs. But do you have a hundred devices to hook up to these ports?
It ain't the DFDR recording limitation that just meets or slightly exceeds the regulated requirement, it's the availability of aircraft system sensors and wire routings that sets the actual limit.
With that said I really don't know what parameters were recorded for BA038