Every reason/excuse for his call up can be batted away with ease.
1. Covers 10/12? So does TJ who has form/fitness on his side and also covers 15. There are probably 10+ players who would make a better like for like Daly replacement - even if they just covered the back three and not 13.
2. Has leadership skills, intensity and raises standards. So did Sexton and he is already there. If coaches haven't been able to do that so far then the wrong coaches were selected.
No matter what anyone says, he is there because his Dad wants him there and that's it. Maybe it's a last chance to work together and Owen's last chance to be part of a Lions tour. It's done now and I suspect the fall out would be much greater if this tour was in SA or NZ where the decision would be more costly. If the Lions win this series it'll be quickly forgotten.
If the Lions win the first two tests I fully expect him to be in the test 23 for the third test if not starting. He may even be involved in the second test at the expense of the Smiths.