Your submission is absolutely spot on if you ask me. It's over a decade I started gambling and I've taken my time to study gambling and how it works which is why I can't be easily influenced into doing anything I do not want to do. Gambling to me should never be seen as a means by which anyone can earn a good living out of it because I've seen people who threaded that path and I also saw where they ended. Like you rightly said, a gambler can only make predictions based on his his experience about whatever he's gambling on and his belief of what is likely to be the possible outcome but he's not just but doesn't have any control of what will be the final outcome. Gambling is mostly influenced by luck so making it a professional engagement is not a healthy idea and the end is always not good
I have seen some peoples around me who have taken up gambling as a profession or have taken up gambling as their source of income, most of them are currently leading unhealthy lives. And this is normal because earning from gambling depends entirely on luck and I think it is impossible to lead a good life depending on anything that depends only on luck. And what I have seen many times and among many addicted gamblers, and their endings were all bad.
On the other hand, skill means someone who has a way that can increase the chances of winning, but if we talk about the type of casino game then I think it's impossible because this is a type of random game that has no track record to learn, and the only skill that can be applied in this type of game is the one that leads to risk management such as prevention or limits. So casino games and sports betting are two different things but luck is still the most important factor in producing victory in the two types of bets.
I think there is nothing to say about skill in casino slot games in terms of gambling, here it totally depends on luck but what matters is that a gambler should be familiar with playing that game in the initial stage.
And in the case of sportsbookies, I would say that skill usually matters a little because prediction often depends on having a good idea about the game and good knowledge about the team, and the more ideas about which one can do sportsbetting better.