I'm supportive of people who resolve to free himself of addiction, when you want to fix your addiction you can think of almost anything to do it, you can cut off your internet, which is not a good idea, you can take a vacation on a place where there is no connection, but you device your way I'm sure it will be effective because its your idea.
When you get out of addiction, the next thing to focus on is to remain out of addiction and play to have fun.
Going on a place with no connection seems the same of cutting our internet out. If one is not a good idea, then the other is not a good idea as well. If he finally gets out of addiction, I think it's recommended to not play again. I know it can start well but things might still turn bad eventually.
It's quite interesting to see the effort you're putting in. Instead of trying to cut back little by little, you're actually cutting off everything related to gambling, preventing you from accessing it altogether.
We only know what works for us. Maybe he also tried cutting it little by little but he still finds himself losing more, so he just decided to cut it all. For me, I have tried cutting it all but I noticed that I feel bad, so I decided to just cut it slowly and I think I'm doing well this way. Even if his desire comes back let say, there is still no way for him to play again because he already blocked all the gambling sites. Time will come that he will not think of gambling anymore. So we can say that his method is truly effective for him.