The sustainability issue with iNat has been discussed elsewhere on the Forum, such as:
https://forum.inaturalist.org/t/long-range-funding-plan-for-inaturalist-is-there-one/8818
although that discussion is a little out-of-date now given that iNat has recently improved its funding status: https://www.inaturalist.org/blog/84393-inaturalist-receives-10-million-grant-from-the-gordon-and-betty-moore-foundation
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