AGPL is as strict as GPL. It's just that GPL allows you to modify the source, serve them as a web application and not have to disclose the code.

AGPL addresses that by putting code distributed as a web application in the same category as compiled code.

If my web server calls out to AGPL software (such as executing a transform on a PDF using Ghostscript) as an external binary is this covered even though the AGPL code is not directly compiled, linked or modified? I'd assume so otherwise it would be a very easy loophole and code could be firewalled into separate modules but I'm not sure what exact language covers this in the license.

It's untested in court.

GCC is written specifically to prevent this sort of firewalling of the compiler to prevent it from being plugged into another piece of software and avoid GPL requirements.

Good to know, it'll be interesting if it ever does get tested.

Even then there's always the analogue/human loophole I suppose, similar to captcha mechanical turks.

You seem to be correct. Still the note about training a deep learning model using the framework, then publishing it without applies.