You can do things in UO that make pet auto-defend not an issue. I just find it boring playing my char in places where there's a low enough spawn count that auto-defend is not an issue.
I don't farm gold or arties or anything really...
In high spawn areas, you need to be able to pull your pet out of a mess sometimes. Prior to these changes, that was sometimes not possible to do because every time your pet is struck by something, it charges back into battle and trained pets can charge back into battle so fast that you sometimes won't know what direction they went (pet movement is server side)
If you've hunted rune beetles at beetlescape using a pack, you know what I'm talking about