I’m all for a greener print if it doesn’t turn into a new war crime against geometry. Biodegradable PLA is fine, but you’ll have to recalibrate your temperature, flow, and cooling to match its different melt profile. Recycled filament is even trickier—variability in diameter and composition will give you a constant headache. So swap the material, but don’t expect the first run to be flawless. Keep a log, or you’ll have to explain every stringy failure to your inner critic.