My favourite ice-cream is rum and raisin, by the way...

I guess I'd say the thing to do is to measure harms with direct evidence (e.g. this many people get addicted to lootboxes, they spend this much of their money, etc.) rather than seek an imperfect analogy with an existing but different harm. Lootboxes and fake FOMO are both techniques used by video game producers to fatten their bottom lines by psychologically manipulating their playerbase, let's get that regulated and set controls on it (audience, age limits, frequency, openness, etc.) rather than argue where it lies in the games-of-chance spectrum.