I've had lots of fun farming these fights unsynched with my FC. There's only 5 of us playing right now so it's been great being able to go do them on our own without needing to recruit others.
If you could only get the rewards with a synced group I'd wager many new players would simply never get them at all. I can't imagine trying to recruit a group to run Ramuh Ex synced an expansion or two from now, even with the unsync option it's rare for me to see it on the PF compared to other fights.
The only content I would be fine with leaving synced forever is stuff like Second Coil Savage which exists solely for the challenge. I'm kinda surprised they allow unsync (and added echo? Haven't gotten it unlocked myself) for that honestly.
