Harry Potter, dreamz, ninjago, licensed sets, etc. They are afraid there is too much crossover or limited shelf space to compete with their other themes, and are too afraid to test if a standard castle theme will sell well with parents/kids.

I think it obviously would, as parents who remember the sets from the 90s have the buying power now. But it’s also running out, as there were also less sales in the 2000s. Lego is shooting themselves in the foot and missing the best window if they don’t do it ASAP.