Stormonu
NeoGrognard
While those 2E campaign worlds may have "failed" because TSR went too far into the weeds with product, to me the basic idea was sound - show the flexibility of the system and give examples of some of the wild and non-standard worlds you put in front of the players. That creativity feels missing in WotC's current "thrive on nostalgia" binge they've been doing.It seems obvious to me.
Remember that the flood of creative settings from TSR back in the day were part of a business model that failed. Having the flagship company produce and solidly support multiple setting lines didn't work. So, WotC isn't going to repeat that pattern.
But they still hold the IPs. So, a few lightweight, one-off products to get folks started in something they might like is fine. But they aren't committing to significant long-term support of any of them.
Look at Daggerheart - the core rulebook has a couple pages on a half-dozen distinctive campaign seeds. I'd like to see more of that; maybe even a book that's a compilation of five to ten page treatment of NEW campaign worlds (and map) for the DM & players to further develop. Throw in quarter-page outlines for adventures for that world (so you get at least four adventure outlines on a page), like you find in the Greyhawk set and let the DM flesh them out rather than burn a whole chapter or half a book on something a fraction might use. If people latch on to one of those new worlds as favorite, WotC could develop it further. They sort of did that with Radiant Citadel, I think they could do more worlds and genres, rather than stuffing everything they can into FR.
If WotC's research shows that people use their own homebrew worlds more than published ones, I think giving their customers the seeds to then flesh out their own world makes far greater sense than retread "the classics" that everyone is going to complain they're doing wrong.