I’d have a hard time proving it but as best I recall from some of the farm safety and farm accident reconstruction classes I’ve attended over the years, the primary impetus for the pesky PTO / seat interlock was folks falling or being knocked off the tractor while mowing and being run over by the bush hog / mower or getting wrung out by the PTO shaft. Quite a messy ordeal. I’ve seen that guy. Never cared to be that guy.
Thankfully mine has a very simple flipper switch that the seat pushes down to engage. Kubota was nice enough to put a bracket for something or other in close proximity so a binder clip and piece of a wooden paint stirrer stick holds it down nicely when I wish to over ride it. I kind of like being able to turn that function off and on, but that’s just me. Particularly with forks, sometimes I pretty much need to stand up for the last little bit to see where the forks are sliding into a pallet.
Coming from the 2N/8N/9N FrankenFord that will start in gear, uncovered PTO spinning all the time (45 years of running it, never seen the cover), no ROPs. And the H with spoked wheels and no fenders (definitely do NOT fall off the seat), row crop tricycle without ROPs, etc. With that background a little seatbelt, ROPs, safety stuff isn’t totally unwelcome.
My brother, who is smarter, richer, and has more hair than me, (and truly a great guy) put a jumper switch on his JD for the same reason. BTW, that pretty much sums up me v my brother. He 3D printed a custom switch box that mounts on the fender adjacent to the creeper switch so neat it looks like it might be OEM. I have a busted paint stick (I shortened it by scoring it with a pocket knife and snapping it with my hands) and a binder clip in the toolbox on mine. Of course he spent the better part of a day and I spent the better part of a minute. Both methods are quite effective.
As Henro alluded, the safest, and only fully effective, safety is consistent application of common sense. No substitute for that.
Hope you get it working as you want and have many years of accident free use.