This feels similar to MC-266543, but I couldn't tell whether or not this part of the issue was resolved, and if this is an intended feature, it is a very strange one. Any mobs ridden while /tick freeze is active will move, and therefore not be frozen.
How to Reproduce Issue
Spawn rideable entity (horse, pig, llama, or if your really fancy, use /ride on another entity)
Run the /tick freeze command
Ride the entity and notice how it is not frozen
Dismount entity and note how the entity re-freezes
Run the /tick unfreeze command and note how the entity then moves normally
Thank you for your report!
We're tracking this issue in MC-266088, 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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