Add option to lock or disable comments for observation, or a user pref

[nimmolo]

I recently reached out to former power user erlonbailey on iNaturalist. A few years ago, this user requested for all their observations to be exported to iNaturalist, and subsequently deleted (!) from MO. (I found him when I encountered something like 20k photos by him that were unattached to observations, and then discovered that he had exactly one observation. @pellaea explained the situation.)

He explained that he left because of contentious comments by, I suppose, the usual suspects, who seem also to be quiet lately on MO. He said he regretted deleting his observations, preferred MO in some ways, and would like the obs to be re-instated. That will have to wait for our planned bulk import from iNat feature, but it occurred to me we also might want to add a feature to lock or disable comments on an observation, or even a preference to disable comments on one's own observations, per user.

What do people think of this idea?