I googled "Comparative Schematology" and immediately found the article at the top published by ACM.

Probably the reason that people referred to  is that this is the location of the refereed article.  (All the experts are on the program committee.)

Some very important mathematical theorems are published only on arXiv. e.g.,  Priority is extremely important.  That is why the Princeton people published their new homotopy type theory results in arXiv.  Tree-killing journals are too slow!  As for reliability, experts don't rely on the dubious blessing of some tree-killing journal.  However, journals are still of some importance in tenure and promotion cases.

The folks at Stanford have leaped so far ahead of the rest of us that we are secretly jealous and struggling to catch up.  Professor Hewitt is probably the top mathematician in his field.50.242.100.195