It was not the case. The main reason is the hard limit for the number of levels, thus - the maximum shared space was limited too. And these levels were not optimally used. To do not waste space, you should always share the maximum possible space, even if you do not have it.
Of course they did, and doing right now. There are benchmarks tools in the repo, so you can check it yourself.
If the PoC would work as expected and will be as fast as already measured, it could be a great upgrade in performance independently of used FS.
This may be addressed by a Community developers right now. Accordingly the GitHub stat of downloads, FreeBSD is less popular than Linux or Windows unfortunately.
Of course they do. Did you tried any of a performance tools
It also stores all profiles which you can analyze.
No, it cannot: refs