I should add the asterisk that my anecdotes on the presumed legitimacy of publishing solely iNaturalist data comes from conversations I've had in the American endangered/threatened plant conservation community. More common or non-American species occurrence data from iNaturalist likely has more legitimacy being used directly in publications.

In the US we have a series of government/NGO controlled databases that house sensitive species data, so often our scientific community has to operate through them to get access to publishable information (of which the raw data is then often obscured, just used for analytics). In my experience iNaturalist data is often a good starting place for determining which government bodies/NGOs a biologist should start reaching out for requesting data access.

I love GBIF and have a priority this year of making sure that my organization plugs-in what we're willing to share via IPT or Biocase!