It will be under water with horrible slow movements, krakens that will one shot you if you dont do a certain thing and to have people even go into this they will put blitzball behind it but like LoV and other content it will be reinvented again and truly not that fun.
@OP: I believe that we will still get the last part of Eureka (lets just pray that not even more items will be put behind this...) but I really hope that they finally listen to the players and not just create Diadem 4.0...
Well I would not call it widely considered decent. We had a huge thread about this when it was released with people discussing Anemos and a lot of it was negative. Even with the train a lot of people still did not like it and others stated that they only like it because they can socialize or that the train makes it bearable. Thats imo not decent. We also had JP posts with over 100 likes that called it dirt. So even there quite some people did not truly like it. We had one poll on reddit (which was made in favor for Anemos since it had two positive and one negative options) and even still only a small amount truly liked it and more found it "meh its okay" and I think around 30% outright took the option that they hate it. And this with a poll that was not even great at all.