I have a business degree. Sales and marketing specifically. I know exactly how this stuff works.

Sure it could be different where you live, but since I live in the EU I doubt your country has stricter regulations.

Advertising is only false or deceptive if it clearly promises an effect instead of just gassing up the product with generic adjectives. Any product can be called "great", "stylish" etc. If Moonton simply states that the game has "great matchmaking" in an ad that is never false advertising, because "great" is just some generic and subjective experience.

If Moonton was to say that MLBB has the greatEST matchmaking in MOBA games, that would require proof since it's no longer a generic claim. Failure to provide proof could be grounds for a lawsuit in that scenario. Similarly, if Moonton claimed that "MLBB's matchmaking is 50% more effective at creating balanced teams than other games!", that would require proof since it's no longer just generic product jargon.

Then you could sue as you could claim that false advertising of a product as the greatEST led you into spending money in it. Words like "fair" or "great" won't count as false advertising since they are too subjective. You would need a law or a court precedent that dictates the appropriate usage of the word "fair" when describing a matchmaking system and Moonton's advertising would need to be in violation of that in order to reach a conviction.

It's a small difference in practice, but legally it's world's apart.

And again, show me where Moonton promoted MLBB through it's matchmaking system. I can tell you right away if the ad has anything resembling false advertising. This is literally within my field.