It comes down to declining returns. Goal line reviews are pretty rare. On the rare occasion when they happen, the camera is going to give you the information you need to make a definitive call 95% of the time. Of the other 5%, most are going to have a negligible impact on the outcome of the game. Of the remaining fraction, where a camera fails to give enough information on an important goal line review, most of those games aren’t going to change the standings. In all of those scenarios, the outcome of the call will be forgotten within a day or so.
Out of some 130,000+ games in league history, only one persists as a controversy in popular memory — the Calgary/Tampa playoff game.
So you’re talking about putting chips all over the ice, and hiring people to install and then operate the system which monitors them, in order to solve for essentially one game every few decades. It’s just not worth the money or effort.