I thought I would add photos of our Thule rack installation on 2018 Subaru Crosstrek as it might help others in selecting crossbars. See photo below of 60" (153 cm) Thule Aero bar. Note the mounting bracket for mounting the Hullivator is mounted on the Aero bar and stays there all the time.
The next photo shows the Hullivator installed. It only takes a few minutes once you get the hang of it. Note how it sticks out quite a bit and would definitely pose a hazard to pedestrians in parking lots.
Here it is in the down position for loading your kayak. Thule recommends minimum 3" clearance with car body. Our installation has 10" clearance. We could easily accommodate 53" Aero bar and still maintain 7" clearance. We would still have problem of Hullivator sticking out too far with 53" crossbar, but I would like to leave room on crossbar to strap the 2nd boat flat. I prefer mounting boat flat mount versus J-racks which are PITA in my opinion. J-rack enables mounting boats tilted to deal with narrow crossbars. I've even seen three boats mounted on cars using three J-racks.