Triassic? So a far higher oxygen and CO2 atmosphere with the resulting mega-vegetation is terrible? Emphysema patients will no longer have to carry around those heavy oxygen tanks, among other benefits of a high oxygen content atmosphere.
Plants will grow huge and become more plentiful - starvation will be a thing of the past.
On the downside, insects will be come bigger, and the reintroduction of dinosaurs will be come a possibility (once some one figures how to decrease gravity so they can stand without being crushed by their own weight), perhaps start with just the smaller ones like the velociraptors ...
Velociraptors will have gold teeth and chains. . . our current velociraptor-equivalents do. . .