In March of 2019, the Dutch regulator compelled Vodafone to publish its wholesale access rates or face a one million Euro fine.

The regulator in Botswana (BOCRA) publishes a public rate card for access to the national fibre optic backbone. Granted this is a state-owned network which removes the complication of negotiating with the private sector but even if we just succeeded with state-owned networks, this would be a big leap forward.

In West Africa thanks to a directive in 2006 from UEMOA, the West African regional economic community established a practice of publishing backhaul and interconnection pricing.

https://blogs.worldbank.org/eastasiapacific/malaysias-need-speed-how-regulatory-action-unleashing-ultrafast-internet