Basically it's very simple.
The self exclude features, is mostly available in many modern casinos like I've seen. So I just don't think its really necessary for the time lock. You just have to use this feature if you can't control yourself or your gambling activities. Most times I just advice one to try his best and control himself. Having self control is what determines your wins as gambler in the long term. Most Gamblers aren't able to control their self and thus end up becoming addicted. Just understand that when you find your self gambling too much, try as much as you can to take a break. This will prevent some losses that are uncalled for.
If that is easy, we will not face many gamblers difficult to take a break. Unfortunately, they don't think to do that especially if they already lost big money. They will continue gambling without think about more losses. Self exclude can be used for a gambler who think he may playing gambling too often so he can try to use that feature. But if he can not control himself from avoiding casino, whether it is offline or online casino, he will return to casino and gambling. That is why controlling ourselves when gambling is needed so we don't have to use that feature and we can also avoid the problem.