Unsure if this is intended or just lack of coding:
Campfires placed on Soil Soul do not become Blue.
Any and every entity that is ignited burns Orange.
Soul Soil fire doesn't spread, but also can't ignite TNT?
Comments 2
Please only report one issue per ticket, also use the search function before reporting an issue. See: Guide: Writing Helpful Bug Reports for Minecraft
For campfires, see MC-170894.