The published package for R4, hl7.fhir.r4.core|4.0.1, has 4,583 JSON files in the package (that does include a few files like index.json, but almost all are definitional items).

The published package for the R4B ballot, hl7.fhir.r4b.core|4.1.0, has 2,685 JSON files in the package (again, including files such as index.json).

With the package missing almost 2,000 items, I cannot complete an evaluation of the specification.