What is Online Gambling?

Have you been paying attention? The requisite characteristic, a payment of Consideration, is present regardless of such abstractions, because play is initiated by the spending of points which are not given free of charge. Additionally, the reason why arcades are legal is they are games of skill, not purely games of luck. If a video arcade held any games of chance with a payout of a prize, and the establishment forbids entrants from bringing in foreign tokens not purchased from the establishment, that establishment is then an illegal house of gambling.

And the other requisite characteristic, a payout, is not present.
"Being happy with your toon's damage numbers" is not a payout, or a measurable benefit.

But, as I said before, if you're so sure Nexon is in the wrong, take them to court. Win a lot of money. Force a change in the game.
None of us like the way gachapon, cubes, and the other items with a "chance" to improve your game status work. We just think Nexon has itself covered, legally. We'd be delighted to be proven wrong.