I've noticed when running python toolboxes ApplySymbologyFromLayer does not work. I've also noticed that it works just fine as a ArcNotebook script.
I've taken notice of the following bugs, BUG-000106281 and it's duplicate, BUG-000108497 and it seems to have been mentioned with arcpro version 2.2.
arcpy.management.ApplySymbologyFromLayer(
in_layer=layer,
in_symbology_layer=rangering_symbology,
symbology_fields=None,
update_symbology="DEFAULT"
)
There's not really much else I can do.