No it isn't; the SPC700 could never handle I/O functions for floppies and joysticks.
Sound chip wise, I mean.
Hell, I'd guess that Jerry could've sounded just as good as, or even better than, the SPC700, but it was never pushed (just like the rest of the console).
Back when Songbird was releasing Protector:SE, they were looking for musicians to make some music for the levels. I didn't get any released of course, but the fact is, your submission HAD TO BE .MOD, 4 channels, no effects except for volume and tempo. Also take into account that the T2K cart rips and the Wolfenstein cart rip and other rips, it's all .MOD format. So Jerry is basically like Paula except it was designed from the get-go for MOD files. You're right in the fact that no one was able to develop better formats for Jag like they were for Amiga, but had they? They would have been EQUALS.
Jaguar = pwn. Except for the amazingly retarded intro screen (which BTW uses that Fairlight orchestra hit sample that was either on the ST-01 or ST-02 disk...actually, I think it was ST-09?)
Also, the PS1 has the bigger brother to the SPC700, right? That's what someone told me before, but I don't know what to believe, I always thought sample playback was handled by the CPU as software.