Like, if Valve do want to keep item trading in (and potentially be used this way is an understatement, these are multi-million dollar gambling businesses), they could at least try to stop them.

Valve's enforcement was one round of C&Ds in 2016 (!), and then some technical measures [0] in 2024. For Valve to take heed the problem, they literally had to have a stage invasion at their esport event [1].

[0]: https://store.steampowered.com/news/app/730/view/41856069942...

[1]: https://internettalk.xyz/blog/cults-vendettas-gambling-how-a... - article I published, Coffeezilla also has a video on this event: https://www.youtube.com/watch?v=q58dLWjRTBE