There are many broadcasting laws worldwide, many quite archaic. Even Radio Garden got meaningfully restricted in the UK (only licensed national radio stations are allowed by a high court ruling). I worry for projects like TV Garden but they are undoubtedly very cool.
A UK High Court ruled in 2019 that websites like TuneIn are distributing illegal music[0]. It went to appeals but the previous ruling was upheld. There hasn't been much clarification beyond that nor very clear enforcement. But the precedent this ruling set makes companies fear repercussions if they accidentally link to a stream that has content not licensed for the UK. To interpret this ruling broadly would be to break the internet[1]:
> The claimants say that a finding for the defendant will fatally undermine copyright. The defendant says that a finding for the claimants will break the internet.
As usual, this happened due to rather rabid approach to copyright by big American labels. They may be legally in the right, though their actions, as always, have meaningful negative externalities. How far they reach in this case is unclear, but TuneIn and Radio Garden both have blocked non-UK streams for UK listeners.
[0] https://en.wikipedia.org/wiki/TuneIn#Legal_issues
[1] https://excesscopyright.blogspot.com/2019/11/did-uk-judge-ju...
It is rather awkward that the US right-holders chose to sue TuneIn in the UK, rather than US radio broadcasters that stream online without appropriate licenses. However, TuneIn was profiting from the premium subscriptions relating to content they knew didn't pass muster legally, and their service foundational was based on such content. There are certainly many things to be said about it. But unfortunately the debate is already settled by the appeals court in the UK.
Overall, the UK TuneIn service was valuable to the public. And it is an example of such value being destroyed by copyright laws. This is yet another topic that many people have said much on.
Wait, what? Receiving foreign web radio streams in the UK is prohibited?!
How is that even enforced?