I very much beg to differ. If you’ve ever been in circuit with a 12 volt car or marine battery you will definitely feel it if you have any moisture on your hands or it arcs onto jewellery, and you will likely receive 3rd degree burns. The direct current voltage isn’t the determinant of injury or pain; it is the cold cranking amperage (CCA), who for a typical car and truck battery will be between 200 and 1,000, delivering an instantaneous power of between 2.4 and 12 kW.
Whether that would kill or not depends on a number of factors including how the victim is grounded, where the leads are attached and main path of the current, and how health the victim was prior to being electrocuted but it would certainly be painful. By comparison, a 240 VAC 40 amp service circuit in your house is perfectly capable of killing an unwary DIY-er, and that is delivering around 7 kW instantaneously.
Stranger