As long as you don’t cross that line, it can be considered entertainment. But if you say you’re playing for fun while raising your stakes, that’s already self-deception.
And that's where the problem is, the line is always crossed, that's something that isn't recent, since we are players we have always crossed the line, because we are risky people and whoever hasn't done it at some point will do it, but for that you have to be clear about many concepts, first the money you are willing to lose, and second the discipline, but in itself, I believe that all of us at some point have crossed the line.