This isn't my area of expertise, but a workaround for incidental shared library symbol collisions appears to exist in the form of ELF symbol versioning. I think this could enable multiple versions of boost to be linked into the same executable, without the symbols from one overriding any symbols from the other. If my understanding is correct, this could provide the benefits you sought from static linking, without foregoing the maintenance advantages of dynamic linking. Not that it would alleviate most of the issues stemming from ABI instability, but I think it would address some cases.
This is easier to do at the source code level by placing exported symbols in a detail namespace whose name is mangled with the Boost version: this is what regex does, and I suspect other libraries too. It has the side effect of reducing support requests from people who accidentally try and link to the wrong library version, as well as allowing to different versions to co-exist. John.