It’s optional content so no. Also I am convinced that iLvl cheese is not that much of a problem and it wouldn’t change anything.
The player base is simply greater for the CT raids. There are many reasons for getting CT.
1. People may be levelling a job and their level is too low to access the next tier;
2. Despite being over levelled and willing to unlock the next tier, one may not have reached the point in the MSQ that allows them to unlock the next tier of raids (along with the tome gear);
3. ftp are limited to CT and HW raids so that eliminates 3 out of 5 series
4. someone may be queuing CT specifically (msq, relic weapon quest or just because)
5. Pure “luck”. Even if the whole team is in 600+ gear and has everything unlocked, roulette could still take you to CT.
As for unlocking the other raids, optional content is well, purely... optional as the name says. CT are the only mandatory raids. There is a lot of content in the game for someone starting to play these days versus someone who had the chance to unlock content over the years. People may want to do their MSQ and unlocking all that side content takes a significant amount of time. I made a new character on the new DC and bought a level boost...there is a daunting amount of blue markers all over the maps and unlocking the optional ARs is not my priority. If/when I get there, I will not unlock Dun Scaith or Tower of Paradigm: I don’t like Dun Scaith and tower hurts my eyes. Someone else may not like 24m raids enough to unlock the others.
Also, a new player may not even know about those raids. The quest givers are not exactly in the most obvious locations. They could move the initial quest givers or add a messenger to areas with high traffic. For example, atm to start the Nier raids quest, you have to go back to Kholusia even though you have no other reason to do so and talk to the little guy in a far corner of the map.
They should also provide greater rewards for the other raids to give an incentive to unlock them and run them. Atm for a reward that is basically the same, you can spend 15 mins in CT or, if your alliance sucks, 1 hour in Orbonne (recently left a group that had reached the 50 minute mark at the 2nd boss as that’s all the time I had). Not everyone can play for hours every day.
You don’t want to do CT? Simply queue for a raid of your choice. You don’t have to use the roulette. The main purpose of roulette is to help others complete content they wish/need to do so take control of it and stop complaining.