Just a guess, but perhaps these card collecting games haven't received the same degree of negative attention because to outsiders the card game aspect obscures

Just a guess, but perhaps these card collecting games haven't received the same degree of negative attention because to outsiders the card game aspect obscures the collecting/gambling aspect. With CS:Go skins it may be more obvious to people since skins are something completely extraneous tacked onto the 'real' game, whereas with the card collecting games the cards are an essential component of playing the 'real' game. Another hypothesis is that video game players who don't partake in loot boxe gambling have become ticked off (perhaps because they perceive the gameplay to be neglected by companies who make their real money from these loot boxes.) These anti-loot video game players may then become activists against loot boxes, drawing broader public attention to the issue. Card collection games probably don't attract/create as many motivated activists calling for regulation and reform.