When do you not "win anything"? Also your dismissal of the Pokémoncard comparison is pretty weak.
While it's technically correct that you are winning something every time you pay for a loot box, I doubt that someone who "wins" a couple of med packs and some duplicate item that they already have would consider it winning. They're not gonna say, "holy crap, I won, no need to keep pumping money into these boxes!"
Also here are three videos. While they do share similarities, one of these is clearly not like the others.
https://youtu.be/qRq2b3siAio?t=279
https://youtu.be/UxkBm4sEoE0?t=354
https://youtu.be/pqW8gJnqhAQ?t=159
Sure, the guy opening the Pokemon cards gets excited when he gets something good but there's no shiny animation and loud noises trying to create an experience that says "this is so much fun, don't you think? Keep going!"
Very poor analogy and somehow you try to not see that you put in stake in a slot machine and can get nothing over and over. Gambling and blind purchase are different.
Instead of trying to argue wrongly that it's 100% gambling it might be best to put forward something else.
I would argue that for anyone who has had any kind of experience with these boxes in the last five years, winning basic loot and med packs counts as basically nothing. Someone who puts 20 dollars into loot boxes and receives med packs, ammo and duplicates would feel like they received basically nothing. But wait..
Maybe if they put in another 20 dollars they might get something really good.
Also I feel like this you won something argument is a "well technically" argument that completely ignores how this impacts people in real life.
"I spent 60 bucks on loot boxes and got nothing."
"Well technically you did get ammo packs."