All I can say is I don't agree with you, but it seems that I have a very different POV toward FFXI. I don't view FFXI as a "raid based MMO" that the entire game is designed and balanced based on endgame raid and the sole purpose of playing the game is to do raid and get gear. ARR was like that and I hated it. I view it more like a virtual world where ppl just live in the game, and raid/endgame being one of many things you do in game. IMO, solo dyna, salvage, solo PW for gil, do AA BC is also part of the game and this game isn't delve only.
There are plenty of solo content that give good rewards. You build R/M/E with dyna/salvage, you can solo PW and sell scoria for gil, not every job can do that. Those are all part of the game IMO. This game shouldn't be 6 man content only.
In ARR, they removed elemental dmg resistance so every DD has equal performance in instance content. If you want that kind of game may as well play ARR. But FFXI is never a game like that, it's designed in a way that some job has better performance in certain situation and you NEED to job change if you're in different situation. If you can't find a situation that your job can shine, you should ask the dev to create the situation that your job shines, instead of asking the dev to change the job so they're all the same.