My initial reaction was what many of you have said; no. Utah is run lock stock and barrel by developers (look at the prison move and point of the mountain as an example) and they'd just sell off every parcel they could to build condos on. But I've ruminated on this for a the past week and have come to a slightly different conclusion.
The BLM sucks, lets get that out of the way up front. I deal with the BLM a fair amount these days, and while some individuals are fine, the organization is just so poorly run from the top that there's no way that individual field offices can really do their jobs in any effective way. Most field offices are understaffed and underfunded. The agency as a whole spends something like 40-50% of its entire budget on litigation, which is insane and a big reason why they don't "manage" the land, they just close stuff. They don't have the money and they don't have the people.
I think that if this case is picked up by SCOTUS, it won't be a clear cut decision. As in, they won't boot the BLM out and hand all the land "back" to Utah. What I think is more likely outcome is that some of the BLM's overreach will be rolled back or curtailed, such as WSA's that have been sitting there for 30 years will be removed and years long "temporary" closures lifted. And perhaps a prohibition on further wide reaching management plans that are opposed by the State on stuff like economic or cultural grounds. So for example, the BLM will still "manage" the land, but if they want to close hundreds of miles of roads that are claimed by a county, the State might get precedence instead of the BLM just being able to close it on their own due to the negative economic impact it would have on the counties tourism industry.
Ultimately, I think that this is a good exercise. I think that whatever the outcome might be, it's going to change the way that our lands are managed and force the BLM to make concessions. Could there be negative consequence from this, absolutely. But I'm choosing to be positive and think that net/net, this could be a win.