Duty roulette - Raids

I'm just wondering : we have Duty roulettes for everything : dungeons, PvP, Trials, Guildhests.
But we don't have any for Raids.
Back in 2.X I could have understand this, as Bahamut was, as EX primals, something that was meant to be tough ! But is it still hard as EX primals now ? I don't think so.

However, not having Duty Roulettes for Raids led us to the point where both Bahamut and the Cristal tower are not visited anymore, and getting a party for them became really difficult nowadays.

So if you do this, here are the good things it could bring :
- newplayers will be able to enjoy Bahamut and CT stories (myself included, as I only completed T1)
- Old players will have a new way to get a few daily esoterics.
- Old players will probably like going back to these places they didn't see for many monthes

Thank you.
If it's not possible, I'd like to understand why.