That is because Empire is much more a character piece. Which really is where Kershner is good, and where Kasden's writing strength is when not limited by Lucas control.

Jedi is an action piece much more like star wars than Empire is. A swashbuckler like star wars but even more juvenile than that first film was.

Jedi made more than Empire. Empire almost cost Lucas everything because the film went three times over budget over time in shooting.

Marquand knew how to do quick and cheap set ups and coming from a documentary background like Lucas, he was much more aligned to Lucas vision than Kersh was.

On Empire as beautiful as the photography is, and that the finished film was marvelous, Kersh almost went to Kubrick style levels in the filming and set ups, totally out of bounds in a Lucas production.