How are these treaties enforced? All international treaties are ultimately based on trust. There is no higher authority, only elective councils of and voluntary commitment to procedures (a.k.a. promises) by sovereign states.
Specifically not even these formal promises have been given by e.g. the United States of America which to this day has signed but never ratified either the VCLT[1] or the VCLTIO[2], so is figuratively giving a lukewarm "let's see about the convenience of that when it comes up".
A 2016 talk by Tribeflame CEO Torulf Jernström about the monetization of mobile games called "Let's Go Whaling!" also caused a bit of a ruffle a while ago.
Ominously delivered with smug smirk, met by smug laughter: "I'll leave the morality of it out of the talk. We can discuss it, if we have time, later."
Web.de was founded in 1995 and GMX in '97. Both now belong to the gigantic German United Internet AG founded in '88 which currently has roughly 10,000 employees and EUR 5.5bn revenue.
https://en.wikipedia.org/wiki/Discord#History