[83GMCK2500]

Ignoring the center configuration, and looking at left and right.

Right-hand image:
Original, 14 bolt 10.5" full floater in your truck.

Left-hand image:
10 bolt
12 bolt
14 bolt w/9.5" ring gear (someone mentioned the 454SS truck, same axle as 81+ light 2500 squares in 8-lug, same axle as GMT-400 heavy half/light 2500 in 6-lug, and GMT-400 light 2500 in 8-lug, vans, lots of apps.)
Dana 44 from Jeep that you're looking at.

Look at the images above, where the loads are carried specifically. In a semi-float they are carried on the end of the axle itself. When I say axle I mean the shaft connecting the side gear in differential to your tire/wheel. In the semi-float configuration all of the rear loading, be it vehicle weight, cargo, tongue weight of trailer...is all carried at the wheel bearing at each outer end of the axles, from that bearing into the outer-most portion of the axle housing. Combine that with the torque that is ALSO applied to drive the vehicle, it become a lot of load along one single component.

Look at full-float diagram. It has a set of opposing tapered roller bearings in the outer hubs that divide and transfer the rear load onto the spindles of the housing. The torque applied to drive the vehicle is the ONLY load that the axles carry in this design. All of the forces, distributed amongst multiple components.

As others have said it is not about any one thing, going, stopping, or carrying. It's about all of them working together and nothing failing.