Strings ("tendons") have their own problems. Wear at bearing points, mostly. You need an opposed pair, too. So there's a motor, a winding drums, and something like a spring to maintain tension. Or two motors and two winding drums, which gives better control.
That's why snake robots have never caught on. They're good painting robots, because they can get into tight spots. But repetitive cycling wears the tendons at the same place on each cycle.
There was a good application - Tesla's snake charging robot.[2] All the complicated stuff is in the pedestal, and you can surround that with concrete to prevent damage if it's hit by a car. The snake part has no motors, just discs and strings, plus the connector and probably a cell phone camera at the end. It can be made easily replaceable, like a gas station hose.
But some people thought it was too creepy.