This arma 3 server parameter view distance option will set every players viewdistance to the admin selected range, remember maybe not every player can handle huge view distances.

description.ext

class Params
{
	class PMC_viewdistance
	{
		title = "View distance (in meters)";
		values[] =
		{
			500,
			1000,
			2000,
			3000,
			4000,
			5000,
			6000,
			7000,
			8000,
			9000,
			10000,
			11000,
			12000,
			13000,
			14000,
			15000,
			16000,
			17000,
			18000,
			19000,
			20000,
			25000,
			30000,
			35000,
			40000,
		};
		// When 'texts' are missing, values will be displayed directly instead
		default = 5000;
		file = "PMC\PMC_setViewDistance.sqf"; // (Optional) Script [[call]]ed when player joins, selected value is passed as an argument
	};
};

PMC_setViewDistance.sqf

private _viewDistance = ["PMC_viewdistance"] call BIS_fnc_getParamValue;
 
setViewdistance _viewDistance;