Which is why I brought up the floating docks. They’ve got that too. Though it works in the opposite direction. The pylons are sunk deep, deep into the seabed. With a concrete footing for heavy docks. And the float docks are shackled too them, or mounted with the pylons passing through them. They ride up and down over the pylons. The idea is to have a platform that is perfectly stable laterally. But can rise and fall with tides naturally. So you can have a platform to tether your boat to that is floating at the level of that boat. Rather than significantly above as at low tide for rigid docks.
And they’re still the first thing to be damaged in harsh weather. And its done that way (rather than having pylons mounted on the dock that fit into some sort of tube on the anchorage). Because the pylons are the only thing that survives when they go. (sometimes, snapped pylons are a thing.). A weak telescoping tether only means its more likely to fail. And these things are more likely to be carried off.
There’s also tremendous risk of damage from waves or flash flooding to anything not firmly anchored. Because it can be battered around rather than the water breaking around it. I’ve seen some pretty robust floating dockage and platforms smashed to bits without ever leaving the structures they’re tethered to. The permanent docking, buildings and pylons they’re attached to? Mostly undamaged.
These things are effectively more complicated, more expensive, less reliable, and less stable houses on stilts.