opendal's compile time isn't very fast (maybe because of async traits). As a matter of fact, I noticed that many features are turned on by default.

Maybe it's better to disable some of them, which are not very frequently used (e.g., ghac, ipmfs, ...). I'm not sure about the criterion. Alternatively we can make all as optional.

This should be a breaking change. But it seems we upgrade major versions quite often, so this shouldn't be a large concern.