Are water passing valves supposed to be hard to open and close?
That is a ball valve that opens/closes with a 1/4  (90) degree turn and YES they are hard to turn. If you want an easier valve to turn, buy one with a longer handle. Valves that screw in use a mechanical advantage, an action similar to a nut and bolt and are  easier to turn but take longer to open/close. And, remember there is a stop that only allows the valve to turn 90 degrees either way. To make them easier you will have to find one that is easier to turn and replace the existing valve with the easier one.