As it criminalizes violence or the threat of violence against property as well as persons, Hobbs Act Robbery is categorically not a crime of violence under the sentencing guideleines. Similarly, the generic crime of Robbery enumerated elsewhere in the guidelines is narrower than Hobbs Act Robbery, since federal Robbery requires imminent danger to the person; the generic crime of Extortion is also narrower, as caselaw requires threats to be directed against the person.
Not harmless error, as the court didn't explain a basis for variance that would account for the resulting variance.
https://cdn.ca9.uscourts.gov/datastore/opinions/2021/08/16/18-30238.pdf