We're way ahead of you. Fuel shutoffs at the firewall have been a mandatory thing for, oh, about 80 years. They not only let the pilot shut the fuel off in case of fire or huge leak or an imminent forced landing, but the mechanic can shut it off so he can remove the fuel filters and carburetor and stuff like that.
Clamping a rubber line is a good way to start it failing. Damages it internally. Besides that, lines aft of the firewall are aluminum, not rubber, since rubber deteriorates and needs periodic replacing. Gets expensive inside the airplane. There are sometimes short sections of rubber line between tanks and the airframe to allow some movement, and they are often found old and cracking, and replacing them can be a pain. The flexible lines are usually found between the engine, which moves in its mounts, and the firewall. And they go bad in five or ten years. I've found those lines hard like wood, cracking, leaking, ready to just fall off. Big problem.
Automatic stuff presents more failure points. Electric or electronic stuff depends on the airplane's electrical system, which many here will tell you can fail at any old time. Automatic stuff is fine on the highway; not so much in airplanes, as a failure can mean an accident, so aircraft automated systems are of high quality and have some redundancy. All of that adds weight and cost, and flying is already expensive.
And automation dumbs down the pilot. ABS--antiskid brakes--are a case in point here. That ABS in your car is real nice and lets you drive safely. It also lends a sense of invincibility on a slippery road, and sooner or later you'll drive a little too fast or brake a little too late on a surface that is a little too slippery, and the ABS won't save you. Nice SUVs and 4x4s in the ditch are a common sight in Canada in the winter, while Grandpa in his old Chevy has slowed down, feels the road, and gets home for supper.
