The problem here is that there is more than two metaphorical people involved: there is the developer, the would-be user, and the evangelist who harangues the developer with "rewrite it in Rust brah" drive-by comments or blog posts about how nobody sane would use memory-unsafe languages/ecosystems without a vibrant community package management ecosystem in the year of our lord 2026.

The last person, I think, most clearly, does "owe" you supply-chain security, in the sense that he bears moral (and ought to be made to bear professional) responsibility for any adverse consequences you may suffer from its lack, though in practice he will probably often protest that he couldn't do anything about it because it's not like he is developer. Whether the developer also owes it is a more interesting question, and I think it greatly depends on what attitude he takes towards the evangelist (does he consider him a nuisance who makes implicit promises the developer is uninterested in delivering, or an ally who raises the dev's profile?).

Long ago, I remember seeing a cartoon which involved a tag-team of two people robbing a third, with A pointing a gun at C and saying "give your money to B", while B comments "I'm really just standing here, but I figure it's best if you do as he says". I'm not sure what exact piece of day-to-day politics this was made to comment on (though it was probably some or another flavour of political violence), but it seems somewhat applicable here as well. The lines just become "accept the supply chain, or suffer my public ridicule" and "I'm just providing the software 'as-is', but you probably should do as he says".