Haiku has great support for its own file system, but most others are only available read-only or not accessible. Providing reliable read-write support to one such file system is a complex task, and needs to be repeated for each type of file system.
This is a companion discussion topic for the original entry at https://www.haiku-os.org/blog/lucian/2010-04-28_haiku_file_system_drivers_any_linux_supported_file_system/