I would counter by saying that entertainment is actually valuable. Gambling and playing games are things that people choose to spend their time and money doing because they are fun. (Obviously taking advantages of addiction is immoral, but that’s a whole other bag of worms).

As for optimizing trading algos, the counter is that making markets more efficient is also valuable to society at large, and that is what most quants would say they are doing.

As you pointed out in some other comments, there are certainly issues with the current system. Though, I don’t think the conclusion is for people to stop working entirely. If that were the case all of these “useless” jobs would go away and we would then ask farmers to give us food in exchange for nothing at all?

I think what might be better is offering more incentives for people to work in industries that make a real positive impact on the world. And in lieu of that, people who feel they aren’t contributing in a meaningful way can try to seek out more meaningful work. And we as a society should support *that*.