You can cycle faster, but that’s at your own risk.

The whole reason to regulate those things is exactly because that's not "at your own risk" since you're sharing the road or bicycle path with other people.

As I see it, in your own space you can do whatever the fuck you want whilst risking only yourself (really, go wild!), but as soon as you're in a space shared with other people where your actions can harm others, then your freedom to do whatever the fuck you want is constrained because others too have various freedoms, not least to not get killed or seriously harmed by somebody else simply because they're using the same shared space.

In practice "indicative" is the same as non-existent.

Sure, thoughtfull people who take others into account will moderate their speed in more dangerous situations, but those people would already do it anyways even in the absence of an indicative maximum and, besides, even those with the best of intention can simply be wrong in their assumption that "this is a safe speed for these conditions" (funny statistic, not quite for cycling but appropriate: around 90% of drivers thing they're "good drivers" whilst thinking most other drivers are "bad drivers") and in a crash it's often not just them who suffer from their misjudgment. Meanwhile, selfish assholes will just carry on being selfish assholes in the face of a maximum speed indication or in fact in the face of a legal speed limit which isn't enforced and just go too fast in order to shave themselves a minute or two in their trip, since assholes only moderate their "what's best for me and fuck everybody else" when forced to (meaning that they MUST get punished if they don't).