The bug
Relates to MC-172209. Unlike hoglins fleeing away from warped fungi when chasing players, piglins that are chasing players ignore zombified piglins or soul fire, and will not flee.
Linked issues
is duplicated by 7
MC-176430
Piglins will still attack you if soul fire is present
Resolved
MC-183659
Piglins other AI activities seem to be higher priority than panicking
Resolved
MC-189871
Piglins don't run from soul fire when attacking the player
Resolved
MC-192585
Piglins aren't scared of soul fire torches when they are angry at the player
Resolved
MC-193150
when piglins agro at you , they ignore soul fire , torch etc..
Resolved
2 more links
migrated
Can confirm for 20w09a, though I think the title should be edited to specify when being hostile towards players. When passive they still do indeed run from Zombified Piglins and soul fire