I don’t think it was done in After Effects, but you could certainly emulate this look in AE. There’s always Trapcode’s 3d Stroke, but you would not get the full rounded look demonstrated here very well. You could use particular and make lines with it.
https://www.videocopilot.net/tutorials/advanced_camera_tips/ shows something like that
Ah, found the one I was really looking for:
https://maltaannon.com/articles/after-effects/growing-3d-vines/
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