Trust is not a binary concept; it has many types, dimensions, criteria, which sociologists studied for decades. A friend of mine has even written her PhD dissertation about the subject. I have dozens of files in my research library about the same, which I will make public once my personal digigarden goes public.
Meanwhile, my take on the “scaling of trust” problem/opportunity is that one-to-one trust can scale, to some extent, in the form of swift trust and “transferred trust”, e.g.: A trust B. C trusts A. When A introduces C to B, there’s some chance that C will also trusts B.
But scaling one-to-multitudes is an issue of different type of transfer that, in best case happens one to community, then community to community. Note easily “scriptable…”