I think that's the point. Outside of very few operating systems and languages with the organization and history supporting them, there's not much that one
should trust. Since you can't validate every package yourself, you have to ask yourself if you trust your counterparty. Do you trust ElementaryOS to do have dozens of people validating upstreams before pulling into stable and correctly doing proper package source integrity steps like Red Hat, Canonical, SUSE, et al do? I know they are Ubuntu LTS based but what are the additional packages and how carefully are they curated, built, and stored?
May the answer is to not use Node or ElementaryOS depending on how important security is to you. May I'm the weirdo for critically inspecting 3rd party libraries before including them and looking at the transitive dependencies they pull along.