"There are only two FreeBSD filesystems that are really useable: UFS2 and ZFS."
Keep in mind that the intense proliferation of different filesystems on Linux is the rare exception. On Windows, you get FAT, NTFS and ReFS, but nobody uses ReFS, and FAT is mostly for USB drives, SD cards and such.
On macOS, the situation is not that much different: They have HFS+, more recently APFS, and they support FAT so you can use USB drives and such.
In practice is not much of a problem. Especially when one of your two options is ZFS. ;-)
Read support is fine, write support varies from nonexistent to merely crippled. One implementation allows you to write to NTFS only in the case where you were overwriting existing bits in a file, and even that was buggy.
ExFAT can be problematic due to corruption. I used to have an external HDD formatted to ExFAT plugged in on my raspberry pi. When crashes occured whilst having torrent open, the disk never fully recovered. I had to constantly run repairs.
For small drives e.g. USB sticks ExFAT is great but for larger drives I'd stay away from ExFAT.
My own anecdota: I haven't experienced this ever with exFat on 20+ USB Flash/HDD drives and I regularly experience crashing Raspberry Pi's (Raspbian OS) and various flavors of Windows.
"but nobody uses ReFS" - citation needed. It seems to come up on the Veeam forums quite a lot which implies to me that an awful lot of data is stored on ReFS.
I wont disagree with you that I do have access to a lot of file systems but I should point out that Linux has a lot of developers and some of those filesystems picked Linux for that exact reason. I like choice and I have lots.
A variety of FAT is also used for UEFI partitions (cheers MS) and you seem to have missed out exFAT which is quite handy.
ZFS is great on physical hardware in some cases and deserves its name but for me: ext4 does the trick. It's just complicated enough, and no more.
Keep in mind that the intense proliferation of different filesystems on Linux is the rare exception. On Windows, you get FAT, NTFS and ReFS, but nobody uses ReFS, and FAT is mostly for USB drives, SD cards and such.
On macOS, the situation is not that much different: They have HFS+, more recently APFS, and they support FAT so you can use USB drives and such.
In practice is not much of a problem. Especially when one of your two options is ZFS. ;-)