Europa Clipper, which weighs about the same, is planned to make the same trip in five and a half years, and could have done it in less than three if it had launched on SLS:
Tony Bruno of ULA wrote a nice blog related to this recently. Most launchers are optimized for either LEO or the high energy orbits/interplanetary and are not really well suited to the opposite mission. See Figure 1 for a nice graphic.
https://medium.com/@ToryBrunoULA/the-secrets-of-rocket-desig...