Yes, “exact” values do have infinite/irrelevant sig figs/precision. Like if I hold up 3 marbles, that’s exactly how many I have in my hand. Or If on the map I know I am describing the location of the exact tree I saw (good illustration above where you can actually visibly see the tree on the map), the precision circle for the tree is not really relevant, only the marker placement is.
But maybe the more typical case for iNat situations is, “I was in this park and so that’s why this pin is in the park, but we did a lot of walking that day, so I’ll just make the circle size a decent chunk of the park.”