The Bug:

Player does not continue riding on a Zombified Piglin they were riding on after the saddled pig they were riding on is converted to a zombified piglin. This is in contrast with Java 24w36a, which ticket (MC-276342) got resolved Works as Intended, thus, creating a parity issue.

Steps to Reproduce:
1) Saddle a pig and ride it
2) Run /summon lightning_bolt ~ ~ ~
3) You will be kicked off the pig once it gets zombified.

Expected Results:

You stay riding on the pig you were riding even after it zombifies without dismounting it.

Observed Results:

You dismount once your saddled pig becomes a zombified piglin.