Gacha and lootboxes (similar in concept) tend to be the worst of predatory microtransactions because they exploit gambling addictions.

"Classic" microtansactions, like freaking Oblivion horse armor, skins, etc, are bad, but you buy them once and you know exactly what you're getting.

With gacha and lootboxes you buy a lottery ticket hoping to get something good. They use rush-inducing casino-style tricks to get you hooked. They obfuscate your real odds and how much you're spending as much as they can.

I believe the difference is that gacha introduces an element of chance, so you spend an in game currency to buy a spin of a wheel where you may get different rewards. Microtransactions could be something like "spend $5 and get this new skin", it's a guarantee. Gacha will be like "spend $1 for a 10% chance at this legendary skin, spend $5 for a 70% chance, etc etc"

gacha have element of chance, but usually speaking, gacha especially in asian games tend to also be tied to some form of power and is not purely cosmetic.

ao its not just purely, i want this character/costume/weapon because it looks cool, but theyres stats attached to it.

western game loot boxes generally sit more often as coametic, so the desire to pay isnt as bad (but can still be bad) but of course this doesnt apply to all western games either. an example of gacha based power is ultimate teams for sports games, which its gacha has players stats tied to them for team building.

gacha and loot boxes are fundamentally the same, but connotatively, gacha usually implies power and lootbox implies cosmetics, but technically not incorrect to use it either way.

if you want a dumb comparison, gacha is seen like trading card games, where power of the card also has value.

lootbox is sorta like sports cards where its collective in nature and really is about rarity/how the card looks

Generally but not always.

Microtransactions = I want the blue shirt, I can buy the blue shirt. The blue shirt can be cosmetic or have power boost.

Loot boxes = I want the blue shirt, I can buy a lottery ticket to maybe get the blue shirt. The blue shirt is just cosmetic. Maybe there is a way to get the blue shirt if I don't get one in X boxes.

Gacha = I want the blue shirt, I can buy a lottery ticket to maybe get the blue shirt. The blue shirt has power boosts. Quite often, if I don't get the blue shirt in a X tickets, I get a guaranteed blue shirt. Also a bit more often the blue shirt needs to be leveled up, using more blue shirts and/or other stuff you get from the lottery.

This is generally how it works, they are exceptions too it of course.

But that is why gacha is its own category, the lottery is required to progress the game and you need a lot of it. There is also usually multiple lotteries with different and the same prices at different % some you can play without spending money, some you need to spend money and some you can play onec in a while without spending money, but the good stuff and higher % are basically always looked in the two latter ones.

The way it is usually used and how upgrading stuff works, is very different between what country makes the game. I don't remember exactly but the three big different ones are, Japan, China and South Korea.

The easiest different to simply explain is usually if you need more blue shirt to upgrade or if you just need more shirts or if you need shirt coins that drop from the game to level up, the shirt or if the shirt can't be leveld up and you need a new shirt instead.

The concept of Gacha predates lootboxes and started as physical real-world vending machines with surprise balls containing little toys or stickers, mainly aimed at kids

They noticed that the mystery drove sales and pretty much overwhelmed 'normal' toy vending machines in a few short years

While the concepts are similar, they had different origins.