Okay, my bad, I found a very clear answer somewhere else today. I'll add it here for archival purposes.
This tutorial explains things better than i ever will
https://artisticrender.com/how-to-use-alpha-transparent-textures-in-blender/The good news is that it's very easy to do. Basically :
- In the Shader editor, create a "Mix Shader" shader. Link the grey "Alpha" dot to its grey dot. Create a "Transparent BSDF" Shader. Link its green "BSDF" dot to the upper green "Shader" dot of the Mix Shader. Link the lower green "Shader" dot of the "Mix Shader" to your principled BSDF green dot. Finally, link the green "Shader" dot of the "Mix Shader" to the green "Surface" dot of the "Material Output" box.
Hope it's reasonably clear, but I can't recommend the tutorial enough anyway.
Thanks y'all!
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