Yup, same with any kind of betting - sport, even draw games. There are obviously stories that someone managed to "game the system", like a man who figured out how to find winning scratch cards (Mohan Srivastava case) or Željko Ranogajec winning in Keno, but the point is that in the first case it was luck + skills, in the second it was overcoming the TOS by creating a lot of fake accounts, that's why the guy had to give his win back (details of the agreement were not revealed).

You bet against skilled people who set the stakes, so, yes, by observing numbers you can win in Keno, but if you comply to the TOS you will not win big money. The only chance to be able to "game the system" is to bet on something that lotteries brokers does not have time to look at, like 3rd Bulgarian bocce league matches.

The problem is that you need to somehow become an expert in 3rd Bulgarian bocce league and the money which are there are generally small.

I was investigating this (again) when AI showed up, as in theory it makes easier some analysis, but the big guys are also using AI.