Indeed, time will never come back but many gamblers do not care about it all, what is in their minds, they just want to play either just for fun or they want to get the money luck desired by gamblers. Doesn't every player who plays gambling use their time well, people who don't achieve anything like you said are most likely too aggressive in their game. Playing doesn't have to be 3 hours or long in a day, in this case we have to manage the whole thing, be it playing time, losses or profits that we get, if we can control all of this of course we can minimize all the risks.
You will just think this way if you use gambling the wrong way. It’s dedicated for entertainment purposes so you should be enjoying your time if you gamble or else you are truly wasting your time.
It’s same idea when watching Netflix, drinking alcohol and other activities that entertain you.
You can’t say that it’s a waste of time if you enjoy doing it.