Anything consumer focused installed after a plane leaves the factory is subject to much less stringent checks. Anything Boeing puts on a plane as stock has to

Anything consumer focused installed after a plane leaves the factory is subject to much less stringent checks. Anything Boeing puts on a plane as stock has to pass review by the appropriate agency of all countries the plane will be sold to. I remember one poor guy, his job was to try and negotiate the necessary agreements for in flight phone calls for every country the 787 would be flying over for the routes of its initial sales. As I recall, he got damned close! It had to be scrapped when some countries wouldn't allow it. Individual carriers can easily enough add it to only flights over countries that they can meet proper regulations for. Much less of a hassle!