I wouldn’t worry too much about iNat’s physical bandwidth/storage concerns, especially if you’re using a Creative Commons license with your images and sounds. I’m not a dev, but probably a bigger burden than storage costs might just be the size of the actual iNaturalist database and what it takes to search, reindex, organize, etc. Each record creates more cells in the database which need to be indexed for search.
I agree with @pisum that the bigger issue is the load on the user community. Try to observe judiciously, and also give back by adding IDs to other users’ observations as well.
As far as I can tell, the original post was not related to iNat’s actual resource use or carbon footprint. If someone is concerned or curious about that, it would probably be best to discuss it in a dedicated thread, although as noted it’s been discussed multiple times before (I found these with a simple forum search):
https://forum.inaturalist.org/t/carbon-footprint-of-inaturalist/11126
https://forum.inaturalist.org/t/live-carbon-footprint-of-the-inaturalist-platform/36768
If you’re concerned about climate change and carbon production, I’d think iNat’s infrastructure is relatively inconsequential. Rather than trying to crudely determine (with really nebulous information, as Ken-ichi explained) iNat’s carbon use, a more efficacious use of time and resources is to effect broad, substantial change via political means, donating to conserve natural areas, and modeling and publicizing behavior and habits that are more impactful at the scale which is needed.