I basically agree with this. I highly value consistent and principles-based thinking.

I used to be the same way as Stallman (starting with premises and following them to their conclusions, however uncomfortable.) But I think we differ in that (1) I wouldn't post about them, (2) I make compromises all the time for convenience, and (3) living life means using imperfect logic and heuristics over incomplete information to minimize the costs of decisionmaking. So it's super silly to imagine oneself as being equipped to start with the "right" premises and to be able to follow them to absolutely correct conclusions.

I honestly think necrophilia is a great extreme point for discussion, but only in places where people want those annoying Big Philosophy Debates. (Reasoning for it being good for discussion: It has a big disgust-to-actual-harm ratio, AND participants can rest assured they're all mutually uninterested in the act. I wouldn't think, "Oh, zeldamaster2002 makes some good points, but do they have unsavory intentions with a corpse?")

That said, Stallman has advocated for the ethics of CSAM, pedophilia, incest, etc. too, so, yuck. ("Uh, does zeldamaster2002 have unsavory intentions with a sibling? They're really invested in this debate.") A lot of the arguments for these assume the event happens in a vacuum, or under extremely and infeasible contrived conditions. I overall think a good ethical law/rule should be an ethical heuristic, and even if we can imagine a scenario where necrophilia is good, it's astronomically more likely to be harmful, so it's good to prescribe against it.

At the very least, this thinking isn't reflected in his political notes. I think he at least has the capacity to weigh matters by importance (whereas I spent 45 minutes trying to summarize my position on necrophilia, an issue which will never matter in my life), but maybe not be expertise. (His posts about disabled actors are about as long as his posts about iOS 14's EU app store changes.)

I think I sympathize with Stallman to a degree, as an autistic "bad ending" I've avoided. I'm quite autistic, but I feel like I've been able to far better internalize the mechanisms and utility of how people interact well enough to get by.