The bug
When riding an entity through a portal, the playersNetherPortalDefaultDelay and playersNetherPortalCreativeDelay game rules are disregarded, making it inconsistent with teleporting through portals alone.
How to fix
It may make sense to change nether portal delay from a game rule to an entity attribute, which would be 80 for players and 1 for other entities by default. Moving a stack through a portal could use the highest value found within the stack.
Thank you for your report!
We're tracking this issue in MC-272357, so this ticket is being resolved and linked as a duplicate.
That ticket has already been resolved as working as intended, which means this is not considered a bug and won't be fixed. Please do not leave a comment on the linked ticket.
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