[Caetano Veyssières]

This script does the trick but it’s not free:
https://aescripts.com/explode-shape-layer/

Or there is one faster way than duplicating n times and deleting all the paths but one for each layer.

You can do what Chris and Trish Meyer say in the page you found:
https://provideocoalition.com/cmg_keyframes/story/pasting_paths_from_illustrator_to_after_effects

and then group each path (ctrl+G) individually, and now that every path is grouped you can transform and animate them individually by clicking on group > transform: Group

And if you want them to have different colors or other parameters, just select all the groups, then click on “add” on the right of “Contents” and select fill or contour or whatever you want and it will add the parameter to every group.

Of course, group several paths if you want them to have the same parameters and animation.