Any derivative works of AGPL-licensed software must also use the AGPL.

How a court interprets "derivative" here makes a big difference, that Drew doesn't seem to effectively counter. I'm not sure why his take on what it means will make a difference to what a judge may think it means.

Until AGPL is tested over and over in court, and all interpretations converge on Drew's interpretation here, it's not safe to have anywhere in your commercial stack.