Internet in NZ used to work a bit like the US does now with one large ISP that is also the network operator and gave exactly zero shits about quality of connections or internationally competitive pricing, except they got greedy and charged their retail arm half what they charged their competitors. Anti-monopoly folks got very pissy about this and managed to get the largest fine permitted by law, forced them to split their wholesale arm off into a separate company, banned them from tendering on the government-funded fibre network (which cost them literally billions of dollars) and then changed the law so that if they did it again there wouldn’t be a cap on the penalty they could impose.
In 20 years we went from ~35th of the 38 OECD countries in internet speed and accessibility to 9th. Markets only work long-term if you actually regulate them
so far