I don't especially care whether there's a formally enshrined right for incarcerated people to be vegan - I'm saying that if we continue to insist upon locking people in cages with an ostensible objective of rehabilitating them and not simply performing retributive cruelty for its own sake, then we must treat the incarcerated people with diligence and respect as baseline. You can't expect for well-adjusted people to emerge from a system of institutionalised dehumanisation, cruelty, and uncaring indifference.

I don't think it's unreasonable to respect an incarcerated person's ethical commitment to not exploiting animals, and to be diligent in providing food of a reasonable nutritional standard which doesn't violate those commitments to consume. Peanut butter sandwiches do not fulfil that criteria by themselves.

I'm not sure what you mean by "my cultists" - I didn't bring anybody here, and I found this thread independently through my own feed.

In order to preemptively address some of your assertions in reply to another person in this comment thread:

This thread is not about you, not about vegans

It's not about vegans, no.

It's about respect for a person's ethical commitments in a scenario where you've deprived them of the ability to satisfy those commitments themselves. My argument would not have to substantively change in order to comment on a person whose religious dietary restrictions aren't being respected by the available options, to give an alternative example.

It's true that the final paragraph of my original response speaks specifically to animal liberation, but that's because I'm passionate about that issue independently of this one. That said, I think my original reply would remain perfectly sound with that paragraph removed if you'd prefer to take it that way.

the fact that a dude who stole billions

I don't think the crime or characteristics of the incarcerated are especially relevant here. My argument would remain unaltered if the incarcerated person was poor, from a marginalised background, and in prison for much less exceptional reasons.

is more important than justice and literally everyone else

I don't think that whatever justice there is to be found in the prison system is nullified by respecting incarcerated people's ethical commitments, and I think that applies to all incarcerated people.

Unless you think we haven’t noticed you’re hiding behind a debate about the importance of punishment, the viability and legitimacy of the prison system and abuses of the U.S. prison system in a situation that has nothing to do with them because you’re trying to promote veganism.

I'm a prison abolitionist first and foremost, and I thought that'd be clear from the overall thrust of my original post - but apparently not. Respect for the incarcerated, their humanity, and their ethical commitments is very much the compromise position.