The widespread commercial availability of polylactic acid was also a significant factor. It's one of the few plastics that can reliably print on an open-framed printer. The cheap i3 and Ender clones just wouldn't have taken off if we were stuck with ABS.
I think PETG would've also worked. Keep in mind neither of those plastics were rare at the time. The filament form factor was essentially nonexistent though, which makes the whole 3d printing business a lot trickier.
It depends on what you mean by "rare". Both PETG and PLA were commercially available when RepRap started, but they weren't very widely used. PLA's biggest use at the time was reabsorbable medical implants, for example. I don't know what people used PETG for in 02005. I'm not sure either of them existed in the 01970s.
Nearly all plastic bottles under 10 metric liter are PET (many 10 liters produced from Poly(methyl methacrylate)).
PETG is modified PET, so it depend on point of view - (glass semi-full or semi-empty). Any way, in Ukraine people recycle plastic bottles into filament, which is considered by printer software as PETG.
> PLA's biggest use at the time was reabsorbable medical implants
And in disposable forks that liked to advertise compostability. It's no ABS but it isn't and wasn't a rare plastic. I'm not actually entirely sure how common PETG was in products back then, but it's by no means a new invention.
