Fixating on one or the other seems like a case of burdensome detail to me.

Details only become burdensome in that sense if they are misused. It is an unimportant detail for the purpose of deciding how to handle life-challenged individuals. But 'burdensome detail' refers to a specific use of details for (poor) predictions that isn't present here.

I'd say there's a good chance of it going either way regardless of FAI versus incremental tech advancement scenario.

An FAI creating bodies for people wouldn't surprise me either. I'm not sure about the 'regrow from dna' thing... that sounds like what we would have to do.