I've been thinking about this a lot lately and it really sucks that it feels like Zenimax Online is abandoning entire mechanics and zones as soon as they're released. Chapters and DLCs are given no chance to breathe in the way that other games receive post launch content for their expansions and DLCs. Take a look at Summerset for example, the closest thing we have to new content is the upcoming Indrik event which is just a standard festival thing for any other game... And I doubt that's happening before Murkmire releases. When it comes to mechanics like thieving, which I'd argue is one of the most interesting features in the game, it seems like the system was released with Thieves Guild over two and a half years ago and it hasn't been expanded at all. I don't think there's been a new sacrament since the day The Dark Brotherhood released, same goes for heists. Imperial City has remained the same since the day it released. Vvardenfell certainly hasn't seen any additions.
Imagine if in Morrowind, you had a couple Dark Brotherhood sacraments that overlapped with Morag Tong contracts and at the very end of it, you got a prompt saying "if you liked this kind of content, you can buy The Dark Brotherhood for 2000 crowns" or if something happened in Murkmire that bled over into Wrothgar and gave people a new reason to go out and buy Orsinium. It'd keep players engaged in previous DLCs/chapters and there's a financial incentive even for ESO+ players who can play through a DLC in a couple hours and call it done.
Ultimately I think this all comes down to their business model because by the time something releases, they're already onto the next thing but as I said before, there's incentive for them to go back and revisit content, rework systems and find new ways to reintroduce it in future content and I hope they do because when I look at the game as a whole, I see so many missed opportunities. It would definitely be appreciated, especially in these major (5-6 month) gaps where if you're not doing the dungeon packs, there's no new content between the Q2 chapter and Q4 PVE-focused DLC.
Difficulty scaling is desperately needed. 10 years. 7 paid expansions. 22 DLCs. 40 game changing updates including A Realm Reborn-tier overhaul of the game including a permanent CP160 gear cap and ridiculous power creep thereafter. I'm sick and tired of hearing about Cadwell Silver&Gold as a "you think you do but you don't"-tier deflection to any criticism regarding the lack of overland difficulty in the vast majority of PvE content being sold.
"ESO doesn't need a harder overland" on YouTube for a video of a naked level 3 character w/ no CP allocated AFKing in front of a bear for a minute and a half before dying if you don't believe me change is needed.