I have mixed feelings on this as it poses questions beyond just whether or not it would be beneficial to revive a species.

When a species disappears from an environment the entire ecosystem changes, if a species has been absent for say 100 years it may no longer be a beneficial addition to the environment it previously thrived in.

A great example of this is the current re-introduction of Eurasian Lynx in isolated areas of the UK, the Lynx has been absent from the UK for over 1200 years and a lot has changed in that time frame, for one previous competition for the Lynx (species of Wolf) are now also extinct and have been for over 500 years, their viable habitat has also shrunk with Human expansion and agricultural developments so we can't even be sure that prey animal populations within these isolated areas would be able to cope with a reintroduced and now invasive predator, which is one of the reasons why progress on this program is moving so slowly.

Whilst I believe it would be awesome to reverse our past mistakes, i'd not support bringing back a species that could only really exist in captivity, it would almost seem like a morbid vanity project or a living example of our previous errors.