More or less, yes. All Lichanura in California are currently considered L. orcutti unless they are in the Otay or Tijuana riversheds of extreme southern San Diego county (and in some of these areas, the two species live in sympatry). The authors do propose some characters to separate the two lineages in the species description. They describe these characters as tentative, but they might be helpful to some. From the paper:
Mean scale counts of both ventral and subocular scales in Lineage A + B are higher (ventral scales ~235 and subocular scales ~3–7) than Lineage C (ventral scales ~228 and subocular scales ~0–2).
Lineage A + B here corresponds to L. orcutti and Lineage C is L. trivirgata.
However, many people ID things without understanding the current state of the taxonomy, or more insidiously, because they think the taxonomy is “wrong.” This happens with the Arizona Mountain Kingsnake complex as well. It’s largely responsible for why I’ve stopped IDing reptiles and amphibians on iNat- I’ve often run into ID-ers who have been rude about these things.