Some SSDs implement TRIM at the firmware level, but Trim support in the fs is pretty much required if you want to use ZFS on an SSD

WTF are you talking about? TRIM refers to only one thing: the ATA TRIM command that gets sent to the drive by the OS. TRIM isn't the same as garbage collection or wear levelling, though it makes it easier for the SSD to do both. It is however completely unnecessary for the drive and filesystem to work together to correctly store data. It's just a performance hint, and one that isn't even that important for many drives and workloads.