I think this is in more versions then just 20w17a As I have seen it in other snapshots, when a Piglin shoots a Zombified Piglin with a cross bow the Zombified Piglins attack the Piglin and kill them. After the Piglin is dead the Zombified Piglin will come after the player.
Thank you for your report!
We're actually already tracking this issue in MC-69032, so I resolved and linked this ticket as a duplicate.
If you would like to add a vote and any extra information to the main ticket it would be appreciated.
If you haven't already, you might like to make use of the search feature in the future to see if the issue has already been reported.
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