On the same end, why make certain content which is pretty relevant exclusive to a playerbase (such as the coil storyline)? To me that's a pretty significant part of the game, moreso than crafting (which requires you to do PvE anyway to get materials)
And even then, they have implemented numerous ways to catch up to crafting and straight up nerfed it at points. Artisan Needles went from requiring 50 HQ turn-ins to a measly 8. You have artisan body pieces for turn ins as an alternative to the crafted melded ones. Specific gathering nodes had their stat requirement lowered so you didn't need to overmeld to get the turn-ins for artisan main hands.
Players have spent their gil and time as a choice to get ahead of the crafting scene before it came more accessible, just as much as the players who have cleared SCoB before the introduction of echo. Do I agree with the SCoB nerfs? Honestly, it's really hit or miss. This is a perfect example of how you could seperate the difficulty between one just for the sake of clearing, and the other for loot. My friends who are new to the game are lamenting that they did not get to experience turn 7 properly because there's no sense of encroaching danger when it came to handling the renauds. At the same time, they're able to at least DF it to get a clear. It's just that the option for both was not made available.
This is applicable to an extent when it comes to FFXIV. How do you get into FCoB? You need to do Turn 9. How do you do Turn 9? You need to clear T5. I'm not sure how it is on other servers, but it's pretty bad here that I rarely ever find a PF for Turn 5. Infact, people that need fill-ins for FCoB at this time practically require you to have at least T12 cleared.
FFXIV, to me, is one of the more story-driven MMOs that I've played (compared to say, WoW). Something as significant as the coils which ties in to 1.0 and how 2.0 came to be is pretty damn important to be incredibly gated with no alternatives (think trying to put EX primals in main scenario)